CORDON SANITAIRETIMOTHY ZAHNFor Mitch Drzewicki, the day began

like most of the previous hundred or so:he was ripped slapdash from a soundsleep by the screech of a tarsapien at theedge of the forest. For a few moments hejust lay there, letting his heartbeat catchup with him and wondering why the hellhis brain couldn't edit out thecaterwauling and let him sleep throughit. Certainly his subconscious hadlearned that trick with the dozens ofalarm clocks he'd gone through in histhirty-six years . . . . With a sigh helooked at his watch, decided againsttrying for the last hour of sleep he'dallotted himself, and climbed stiffly out

of bed. The not-quite-warm-enoughshower finished the waking-up process,and by the time he'd wolfed down aquick breakfast he was almost over hisgrouch. Coffee cup in hand, he steppedoutside for a breath of fresh air and afinal settling of nerves.

A ritual that nearly always worked . .. because whatever Pallas lackedregarding the courtesy of its indigenousanimals, it more than made up in beauty.The forest surrounding their littlesettlement had an unusual feeling ofvitality about it, both in the way itpressed right to the edge of theirprotective herbicide ring and in itsunashamed delight with bursts of color.In the six months since the four men and

two women of their study team hadarrived here Mitch had solved some ofthe botanical puzzles behind the ripplesof red and pale orange that sweptthrough the ginkgap and manzani trees'leaves every couple of weeks, but hewas a long way from a completeexplanation of the whys and hows of thephenomenon. Only three monthsremained until the university-hired shipwould come to pick them up; and despitethe normal strains their group wasstarting to feel, Mitch almost wished itwas possible to call across the light-years and ask for an extension. It wasalways like this, he knew fromexperience: study expeditions werenever long enough for anything but a

tantalizing taste of a new world'sphytobiology. Still, it was possible thatafter he published the papers from thistrip some other university would decideit worth its while to fund another Pallasstudy, and if so perhaps he could talk hisway aboard. Unless a more eminentbotanist decided to bid for such a slot . .. but perhaps by then Mitch would haveenough prestige himself to get everyfield trip he wanted. Dreamer, he toldhimself; and draining his coffee cup heheaded back inside to the biology laband the day's activities.

The first and most pleasurable ofwhich was going to be saying good-morning to Kata Belen. The petitebiologist was already up, hunched in

familiar posture over her work table asshe fiddled with her recorder andcomputer terminal.

" 'Morning, Kata," Mitch said, comingup to her and looking over her shoulder.The computer displayed a wiggly graph;some kind of spectrum, he guessed.

Kata looked up and smiled. "Well, hi,Mitch. I thought you were going to sleepin today."

"So did I. I really think you shouldcancel Swizzle's wake-up service." Shechuckled, the action accentuating the tinycrinkles around her eyes. She'd oncecommented that the lines made her lookdistinguished, but Mitch thought she wasmuch too cheerful to approach any kindof academic stodginess. "You're the only

one that tarsapien wakes up," she said."Swizzle's always up ahead of time,sitting quietly and munching his manzanifruit, for all the world like he's waitingfor the morning news to start."

Mitch glanced over to the cage thatdominated the far wall of the lab. Kata'spet- cum-test subject was anything butquiet now, his long arms swinging himthrough and around the makeshift junglegym with unlikely speed and grace. "Ihope you don't intend to put leadingsimiles like that into your report," hewarned Kata. "Lyell's firmly convincedthe tarsaps rate a four at the most on theBateson-DuPre. Not high enough foranything but the most rudimentaryinformation exchange."

"Well, Lyell's just wrong," she saidfirmly. "His sole criterion for that is theBateson neural dexterity index, and allthat really says is that tarsapiens aren'tanywhere near the tool-building stage ofdevelopment."

"I thought you'd taught Swizzle to usesimple tools," Mitch said, looking backat the cage. Resembling nothing so muchas a chimp-sized Terran tarsier withtwin-thumbed gorilla arms, Swizzlealways seemed to him more akinemotionally to a canine puppy. Certainlyhis face—all eyes, mouth, and nostrils—never seemed to show the seriousnessMitch had often sensed in borderline-intelligent animals. Possibly one reasonthe forest was so pleasant, he thought

suddenly: nothing existed on Pallascapable of exploiting its resources. Atleast not any more. The scattered ruins . .. but those were the archeologists'

worry."Tool use per se is only part of the

Bateson index," Kata said, breaking intohis drifting thoughts.

"Most of it's concerned with cerebraland fingertip neuron density and firingspeed, and in those I concede thetarsapiens rate relatively low. Besideswhich, whether Swizzle's really usingthose tools is still pretty debatable. But.Communication skill is also part of theBateson-DuPre, and I think I've finallyfigured out what the tarsapiens aredoing."

She tapped the pattern on hercomputer display. "The screeches allsound the same to us, but the ultrasonicpattern fluctuates like crazy as the soundhits peak volume and then trails off. I'mguessing the first, more static segment ofthe howl is something like personal ormaybe territorial identification, and thesecond is then whatever message isbeing delivered." Tapping a key, shereplaced the graph by a series of others,all showing the basic pattern she haddescribed.

"You may be right," Mitch agreedcautiously, "but Lyell's going to wantproof."

"He'll get it." Blanking the screen, shetyped a short message into her private

log and stood up. "I've got a new routinein mind for Swizzle, one that ought tobounce Lyell's guesstimate up at least acouple of points. Want to watch?"

"Sure." Sliding into one of the otherchairs, Mitch watched as Kata crossedto Swizzle's cage and extended a handthrough the mesh. The tarsapien leanedforward, his floppy nostrils moldingthemselves briefly around her wristbefore he rocked back on his haunches.At one end of the cage was a slidingdoor leading to a transparent, three-dimensional maze with a small controlbox mounted on one wall. Kata steppedto the latter and began pressing buttons,and Mitch found himself wondering—again—what in starnation she was doing

on Pallas with what could only bedescribed as a second-class universitysurvey team. As a botanist, Mitch'sprofessional interests overlapped hersonly slightly, but even he knewsomething of her reputation and widerange of accomplishments. Why wasn'tshe with some major planetarydevelopment corporation, or at the veryleast one of the top megaversities?

The answer, of course, was LyellMoffit; but there were several differentflavors to that answer, not all of themespecially palatable. Certainly Lyellwas one of the more gifted persuaders hehad ever run into, as well as one of themost persistent; Mitch had turned downthe genial biologist/physician's two

previous recruitment pitches, but thathadn't kept the other from coming back athird time. Certainly too the name LyellMoffit, though relatively fresh on thescene, was becoming more and morerecognizable, and not only among thescientific community. Mitch had asneaking suspicion that at least one ofthe expedition's six members had joinedin hopes of slingshotting a saggingcareer with the aid of Lyell's growingreputation.

But Mitch rather thought Kata'sreasons were more of a personal nature .. . though it was none of his business, ofcourse. Nor likely ever would be. Katafinished her programming and moved tothe sliding panel separating the cage and

maze. As if that were the signal he'dbeen waiting for, Swizzle scamperedover to the panel and sat thereexpectantly. "All right, now," Kata saidto Mitch over her shoulder, "I've set up apath with drops of jasmine through holesin that pipe network in the plastic.Watch."

Pulling on a rope, she raised thebarrier. Swizzle was through the holelike a furry shot, his nostrils flaring liketwin vacuum cleaners as he grabbed tinyhandholds to pull himself up a longvertical shaft. Mitch watched himnegotiate a right-angle turn, drop down ashort segment—and come to an abrupthalt. "Lost?"

Kata shook her head. "He's blocked

by a sliding panel. Let's see if he canfigure out how to get it open."

But after a couple of minutes it wasclear the tarsapien wasn't going to do so."Oh, well," Kata sighed. "It wasn't amajor part of the test, anyway."Touching a switch on the control box,she sent the barrier sliding upward outof the way. As it moved, the overheadlights reflected briefly from it, givingMitch a glimpse of two hand-sized slotsin the bottom which Swizzle could haveused to raise the panel himself. With theobstruction gone, the tarsapien rapidlycompleted the maze, ending up at the farend and three stalks of pora grass.

Kata closed off the maze and openedthe tunnel that would enable Swizzle to

return to his cage, then walked back toMitch. "He'll get it eventually," she said."And when he does, Lyell and I willhave to spend another couple of dayssetting up nets out in the forest."

"Ah," Mitch nodded. "You'll trapanother tarsap and see if Swizzle cantalk him through the maze."

"And what exactly will that prove?" adeep voice asked from the door, andMitch turned as Lyell Moffit saunteredinto the lab.

There was no question whatsoeverthat Lyell was leaving in shreds thepopular image of scientists as a sub-species of hominid—superhuman inintelligence and language, subhuman inpersonality, taste, and social skill. Even

on a Field expedition a dozen light-yearsfrom the nearest newscaster, Lyell wasimpeccably dressed, his wardrobecomplemented by his easy smile andnatural charm. Mitch had been somewhatsurprised when he found the othermaintained his image off-camera as wellas on; only gradually was he beginningto admit that Lyell's charisma wassimply a part of the man himself. Allthat, Mitch thought glumly, and a top-class scientist, too. Some people have itall. Kata had turned toward Lyell, but atthe moment seemed entirely unconsciousof his charm. "What do you mean,what'll it prove?" she snorted. "It'llprove the existence of detailedcommunication between them, that's

what.""Like communication between bees?"

he countered dryly."Not at all. This kind of maze and

trick door are completely out of theirnormal experience. They'll need toexchange abstract information—and theywill."

"Only if Swizzle can be persuaded tocooperate." Oddly enough, Lyell didn'tseem to be worried about the threatenedattack on his theory. "You'd better makeit worth his while to give any newcomerthe right information. A reward of hisown, I'd say, for getting the other throughthe maze." Kata's eyes had taken on aknowing look. "Uh- huh. So you do thinkthey're intelligent. Your famous devil's

advocate role, I suppose?"Lyell winked at her and turned to

Mitch. "Kata's worked with me before.She knows that half the results mypeople get are inspired by themonomaniacal urge to prove somethingI've said is pure Frensky moss."

"We've yet to make him admit outloud that he does it on purpose," Kataadded, sending a mock glower in Lyell'sdirection. "Usually he tries to claim he'ssimply dumber than the popular mediamake him out to be."

"Well, I am," Lyell said, managing tolook innocent, hurt, and amused all atonce. "All that aside . . . when do youwant to start setting the nets?"

"Any time," Kata said. "We've got

room for a temporary cage in theEndurssons' lab, and if we can get afemale I'll want to do some studiesbefore letting her into the maze. A fewdays' worth, anyway—plenty of time forSwizzle to master the barrier trick."

Lyell pursed his lips. "Rom won't behappy if he and Shannon come backearly and find a tarsap sitting on hisisotope counter."

Kata shrugged. "The only otherchoices are Adler's lab, the commonroom, or one of our bedrooms. You wantto tell Adler he's going to have to moveall those neat piles of rocks he's beenmaking in order to accommodate aguest?"

"Besides which," Mitch put in, "the

Endurssons aren't likely to come backahead of schedule. Even if the ruins theyfound peter out faster than they expect,Rom'll find some reason to stay out therethe full fifteen days."

"Um," Lyell said noncommittally . . .but Mitch saw the corner of his liptwitch. Rom Endursson was the thorn inLyell's organizational flesh, theexception to the rule that Lyell's teamsbubbled with harmony and professionalcamaraderie. Rom was a quiet, moodyman who spent little of his time and evenless of his attention on the others. AdlerZimmerman, the geologist, had oncesuggested that after twenty-five years ofdigging around the leavings of deadcivilizations Rom may simply have

forgotten how to deal with living humanbeings. Mitch privately thought thattheory simplistic; but whatever thereasons behind his personality, Rom wasvery definitely the type who improvedsocial gatherings mainly by his absencefrom them. Fortunately, he seemed torecognize this effect and spent as muchtime as possible at the handful ofsuspected ruins the original discoveryteam had spotted from space. Mitchsometimes wondered how Shannonstood him; but then, she must have hadsome idea what she was getting intowhen she married him. The fact they'dbeen together for ten year's now impliedshe saw something in him the otherswere missing.

"All right," Lyell said, breaking intoMitch's thoughts. "I need to wait acouple of hours for some culture platesto come out of the autoclave, but anytime after that I could give you a handwith the traps. You'll need the morningto get the nets deodorized, anyway."

"Not to mention assembling the othercage,"

Kata agreed. "We should be able tohead out right after lunch, though."

"Fine. Well, if you'll both excuse me,I have some tissue samples to analyze."With a nod at Mitch, he headed offtoward his own lab table.

"Anything I can do to help?" Mitchasked Kata as she signed off herterminal.

"No, thanks," she told him. "The netsand caging material's all together out inthe number three shed; I can bring all ofit in on a single dolly. See you later."

"Sure." Mitch watched her leave theroom. Then, with a glance at the back ofLyell's head, he crossed over to his ownwork bench, piled high with lichensamples he'd spent the last weekcollecting. Should I tell her how I feel?he wondered for the umpteenth time—and for the umpteenth time the sameanswer came back. No. I'd just bemaking a fool of myself Anyone who'sgot Lyell doesn't need me. And puttingKata out of his mind as best he could, heset to work cataloging his plants. It wasactually a couple of hours after lunch

before Kata and Lyell headed outside;but for Kata, as always, the joy of beingout under the open sky made any and allpreliminaries worthwhile. She enjoyedthe lab, of course—the intellectualexcitement of coaxing the secrets out ofsome new organism—but it was for thefield work that she'd gone into biology inthe first place. To tramp alien soil; tosee, smell, and touch alien plants andanimals in their own unique environmentand ecological structure ... it seemed sonatural a joy that she still found it hard tounderstand people like Rom Endursson,who treated all living things with equaldisregard as he hunted his long-deadartifacts.

With forested areas dominating the

Palladian landscape, Lyell had insistedthey set up shop in that particularecosystem, a demand that had reportedlybrought frowns to the faces of those incharge of the expedition's budget. Lyellhad ultimately prevailed, but the extramoney for clearing out trees andundergrowth had had to come fromsomewhere, and the relatively crampedcentral building was the result. Kata hadoccasionally missed their usual self-contained structure—especially whensloshing through the mud to one of theoutside storage sheds—but all in all sheconsidered the trade-off a reasonableone.

"Where do you want to set these up?"Lyell asked as they passed the circle of

sheds and started across the ten-meterstrip of empty ground separating thebuildings from the edge of the forest."Same places as the last time?"

"More or less," Kata nodded, wincinginvoluntarily as her feet crunched the drysoil underfoot. The dead ring—their"cordon sanitaire," as Adler called it—had been saturated with a potentherbicide to keep the forest fromregaining its former territory. Perfectlysafe; but her feet somehow refused tofeel comfortable walking across poison."I haven't seen any evidence thetarsapiens have changed their habits, sothose sites should still be the high-trafficareas."

"Agreed."

The local section of forest was nearlydevoid of such obvious features asstreams, hills, and natural clearings, butradar and Lostproof transponderreadings had long since mapped theground's more subtle undulations.Combined with Kata's record of theoriginal trap sites, the task reduced tolittle more than an afternoon's stroll inthe woods. It should have been anenjoyable time . . . but somehow Katafound herself unable to relax as the twoof them moved in a rough circle aroundtheir clearing. Something in the air feltodd, though she couldn't for the life ofher pin down what it was. Twice shealmost mentioned it to Lyell; both timesdecided against doing so.

They were setting the last net when afull-bodied tarsapien screech split theair from a dozen meters away. "Abouttime," Lyell commented, glancing thatdirection. "I was starting to think all thetarsaps had gone on vacation."

"They have been unusually quiet,"Kata agreed, realizing suddenly that thatwas what had been bothering her. "Yousuppose there's a heloderm loose outhere?"

"Could be," Lyell said slowly,drawing the half-meter-long lightningrod sheathed at his side and adjusting itspower setting. "That screech had a lot ofpiercing ultrasonic in it."

"Yeah," Kata said, drawing her ownweapon. The single communications

point on which she and Lyell agreed wasthat high ultrasonic content signaled thepresence of an enemy. "We going to besmart and make a dignified run for it?"

"Let's take a short look around first,"Lyell suggested, easing a bush asidewith his rod. "I'd very much like to takea heloderm alive."

"Lyell, that's crazy. We don't knowtheir poison won't hurt us."

"Oh, sure we do—the tests on thatdead one's venom, remember?"

"The electric shock could havedegraded the chemical," Kata argued;but Lyell was already moving cautiouslyforward. Gritting her teeth, she nudgedher lightning rod to full power andfollowed. They'd covered perhaps five

meters and Kata was probing carefullyinto a nearby pora-grass thicket whenLyell abruptly jerked backwards with ayelp of surprise and pain. "What?" Katasnapped, trying to get around in front ofhim.

"My arm— ahr!" he grunted again,lurching sideways into her and throwingthem both off balance. Which may havesaved her life. Even as she took a stepbackwards to try and support his weightsomething whistled past her ear andthunked audibly into a tree trunk behindher. They were being shot at!

The total impossibility of it threw hermuscle coordination all to hell, sendingboth of them crashing down into theundergrowth. "Lyell!" she hissed.

"Where were you hit?""Right arm and shoulder," he gritted.

"Feels . . . strange." Another shotsnapped at the leaves above them."We've got to get out of here," she said,looking around as best she could withoutlifting her head. Her lightning rod wasstill gripped in her hand; Lyell's wasnowhere to be seen. Not that glorifiedcattle-prods would be a lot of use,anyway. "Can you crawl?"

"But who—how—?""Never mind that," she snapped,

tugging at his arm. Don't go foggy onme, Lyell, she pleaded silently. "Let'sjust get out of here."

Two more shots whistling overheadunderlined her words and seemed to

snap Lyell out of his torpor. Movingawkwardly on knees and elbows, hebegan to crawl back the way they'dcome. Kata followed, tensing for theshot that would rip into her own body . .. . Surprisingly, the shot never came.Another tarsapien screech sounded,farther away this time, reminding Kata ofthe heloderm that might still be skulkingabout. It hardly seemed importantanymore, though, and she waited untilshe and Lyell had traveled a good fifteenmeters before wriggling her jacket offand raising it on the end of her lightningrod. There was no response, and aminute later she cautiously sat up."Looks clear," she whispered, helpingLyell up. "Can you make it back to the

camp?""Sure." He had a funny sort of look on

his face and he was gripping his rightarm with a white-knuckled hand, but heseemed steady enough on his feet.

"Okay." Kata glanced at her Lostprooffor the direction and got a good gripunder Lyell's left arm.

"Let's go. Quietly."And as they set off she sheathed her

lightning rod and pulled out hercommunicator. The others had to bealerted.

Lyell's knees were starting to buckleby the time they reached the edge of theherbicide ring, but Mitch was watchingfor them and came out to help the lastfew meters. "Are you okay?" he asked

Kata as he took some of Lyell's weight."Yeah," she puffed. "Adler make it

back all right?""He's in the common room getting the

medkit laid out." Mitch was veryobviously bursting with questions, butrestrained himself well. "Lyell, how doyou feel?"

"Not much pain, but my arm feelsfunny," the other said. "I can feelsomething solid in there, too."

"All right, just take it easy till we getinside." Mitch opened the door andtogether the three of them eased throughit.

Adler had finished preparations in thecommon room when they arrived andwas pacing nervously by the window,

one of the expedition's only two laserpistols belted at his side. He came overas they got Lyell seated. "Lyell, what'sgoing on here?" he demanded. "Mitchfed me some nonsense about a sniper?

What kind of crazy story is that?""Wasn't any of my doing, Adler,

believe me," Lyell grunted as Kata easedhis arm out of its sleeve.

"Doesn't seem to be any blood, doesthere?"

"Not much." There was a little,though, she saw, as if he'd been pokedwith a needle. "Mitch, hand me thefluoroscan, will you? Thanks. Now . . .ah. Wumph." She ran the hand unit overhis shoulder next, feeling her jawtighten. "They're there, all right. Two

little needles, a few millimeters long. Inpretty deep, too."

" I could have told you that," Lyellsaid dryly, wincing as Kata probed withher fingers. "You feel up to going in andgetting them out?"

"Me? I don't have a medicalcertificate."

"Well, I can't very well operate onmyself," he countered. "Just pretend I'ma frog or rhesus."

"But—""Don't argue!" Lyell snapped. "My

arm doesn't feel this way solely becauseof shock. Those needles are puttingsomething into me, and I want them out."Gritting her teeth, Kata nodded andreached for the local anesthetic.

It wasn't as bad as she'd thought itwould be. Focusing on a few squarecentimeters of skin as she manipulatedthe probe, she was indeed able to almostforget it was a human being she wasworking on. Still, it seemed like foreverbefore she dropped the second needleinto the gauze pad Mitch held for her.

"There," she said, expelling her breathin a sigh of relief.

"Good job," Lyell grunted, touchingthe skin gingerly. "I think we should goto the biology lab right away and plugme into the blood analyzer."

"Right." Kata glanced around, noticedfor the first time that they'd lost one oftheir number.

"Where's Adler?"

"Checking to make sure all thewindows are latched and watching foryour sniper to stick his nose inside thecordon," Mitch told her. He'd rubbedsome of the blood off the needles andwas holding the gauze pad up to thelight. "If that's really what's out there."

"What do you mean, 'if'?" Katasnapped. "What do you think those thingsare, tarsapien toenails?"

"Could be the seeds of some plant,"he shrugged. "Pine needle shaped,thrown from a branch by the wind or thepassage of some animal. Sort of acombination samara and cocklebur."

"Ridiculous—the speed they musthave been traveling—"

"There's an easy way to settle this,"

Lyell interrupted mildly, standing up."Run the needles under a microscopeand look for Palladian-type cellularconstruction. If there isn't any—well,maybe Adler can run a composition teston them."

"Lyell, aren't you playing thedispassionate scientist part just a littletoo far?" Kata asked, glancing oncetoward the windows. "There's someoneout there shooting at us. Shouldn't we bedoing something to defend ourselves?"

"Adler's wearing our entire arsenaluntil the Endurssons come back," hepointed out. "As for defenses, whatwould you suggest we do? Sandbag theentrance? Rig a defensive force field outof our meson microscope and

centrifuges?"Her despair must have showed on her

face, because Lyell smiled slightly andlaid a hand on her shoulder. "It's not asbad as it looks, though— really it isn't.I'm sure you agree our assailant couldhave cut us both down long before wegot back here if he'd either wanted to orbeen able to. The fact that he didn'timplies we've got some breathingspace." He glanced at the bandage on hisshoulder. "And in that case our toppriority is to figure out just what we'reup against here." It took a few minutesfor Kata to get Lyell connected to theblood/tissue analyzer, about the sametime it took Mitch to clean one of theneedles and get it under the microscope.

"Here goes," he announced, flipping onthe projector.

Palladian cellular structure differed inany number of ways from that ofterrestrial flora and fauna, but even so itwas instantly obvious that the needle hadnever been part of an organic structure.Smooth and metallic, it was equippedwith tiny fins that had the look ofmathematical precision about them, anddespite all it had been through the tipwas still perfectly sharp. Long, thinpores, symmetrically placed, seemed tolead through the skin to a darker shaftbeneath.

Mitch was the first to break thesilence. "I think," he said quietly, "thatwe're in serious trouble."

"The understatement of the day," Lyellsaid. He stared at the needle's image amoment, then shook his head. "This justdoesn't make sense. We know the tarsapshaven't got anywhere near enough brainsor technology to make something likethat, and there simply aren't any traces ofanything more advanced down here."

"What about those ruins Rom andShannon are working?" Mitch asked.

"I mean recent traces," Lyellamended. "Rom dates those structures asat least three hundred years old. That—"he gestured at the screen—"ispractically new."

"Is it?" Mitch pulled out hiscommunicator. "Maybe Adler will beable to tell us." The geologist, when

consulted, looked skeptical. "That's apretty small sample to get bothcomposition and age from."

"Just pretend it's a sliver of unknownore," Lyell said, his eyes on the bloodanalysis data that was starting to comein.

Adler sighed. "Ill try. Mitch, you'dbetter take over sentry duty. Here's thelaser; keep your comm ready."

The two men left, and Kata stepped toLyell's side. "How's it look?"

"Strange, but so far doesn't seem allthat dangerous." He pointed. "The stuff'sgetting into my red cells, but I don't seeany effect on oxygen transport. Wait—here comes a preliminary molecularstructure."

Kata watched with growingfascination as the foreign moleculebegan to appear. It was nothing sheimmediately recognized; and yet—"Anazido group," she said suddenly, tappingthat end of the schematic. "That settles it—this is a poison."

"Maybe," Lyell agreed, tight-lipped."Still . . . seems pretty slow-acting."Kata was already keying the analyzer'sscrubbing capability. "Try to relax," shesaid, double-checking her coding. "It'lltake an hour or so to flush the stuff out ofyour system. How do you feel?"

"Actually, a little better. I don't reallythink this drug was meant specificallyfor use against humans."

"Let's hope not." Kata hesitated, then

removed Lyell's communicator from hisbelt and placed it on the table beside hishand. "If you feel any change, hit theemergency switch and I'll come running.I need to go see how Adler and Mitchare doing."

"I'll be fine," he assured her. "Let meknow what Adler finds out." She noddedwordlessly and left.

Adler's geology lab was just a shortwalk around the building's central hub,but Kata passed it by. Mitch would becircling the outer areas on guard duty,and it was Mitch whom she wanted tosee. She found him by the exit door,staring out the small window with hishand resting on the laser's grip."Anything out there?" she asked.

"Apparently there is; but it's notshowing itself." He turned to look at her,and she was startled by the tightnessaround his eyes. "How's Lyell?"

"The darts were poisoned, but thedrug doesn't seem very virulent. It'sbeing scrubbed out of his blood now."

Mitch nodded. "You're taking thispretty calmly," he said.

She opened her mouth to deny it, butno words came out. He was right, sherealized suddenly; so far her physicaland emotional responses had beentotally on a scientific level. "I supposethe emotional impact just hasn't hit meyet," she said at last. "I had to get Lyellback and then take care of him . . . ." Sheshook her head. "You've had more time

to think. What do you make of all this?""Oh, hell, I don't know." Mitch turned

back to the window. "Lyell's right—nothing that's native here could havemade those darts. We've got to bedealing with an outsider, maybe asurvivor of a space ship wreck orsomething."

"Injured, perhaps, and not mobile?"That could explain how they'd escapedso easily. But—"Surely theseismographs or weather satelliteswould have picked up traces of anycrash or forced landing." Mitchshrugged. "The only other options I'vecome up with are an old survivor fromone of Rom's ruined towns—a very oldsurvivor—or else someone sent

deliberately to drive us off. Take yourpick." Kata grimaced. "So what do wedo?—hole up here and hope he'll goaway?"

"For three more months?" Mitchshook his head. "I don't relish the idea ofrunning through a hail of darts every timewe need something from one of thesheds. And that assumes he doesn't haveanything more powerful."

Kata felt a shiver run down her back."Mitch . . . I think I'm starting to getscared."

"You're in good company." Takingone final look outside, Mitch took Kata'sarm and started back toward the biologylab. "Come on; let's go talk to Lyell.Guarding the door like this is probably a

waste of time, anyway."Adler had also returned to the lab by

the time they arrived, his bristlyeyebrows knitted together inconcentration. "If I could have the otherneedle as well," he was saying, "I mightbe able to get more information."

Lyell shook his head. "I want that oneto do a better analysis on the drug it'scarrying." He looked up at Mitch andKata. "Anything?"

Mitch shook his head. "Nothing pastour perimeter except forest," he said."Lyell, it occurs to me that this place isabout as defensible as the far end of atarget range. Why don't we get Rom andthe Sunray back and get out of here?"

"And go where?" Adler snorted. "We

don't even know what it is you want usto run from."

"Peace." Lyell raised his hand, cuttingoff Mitch's own retort. "I indeed plan tocall Rom and Shannon back, but not forpurposes of escape. I believe what wehave here is a castaway, a victimperhaps of a space accident, and I haveno intention of simply flying off andleaving him." Almost exactly what Mitchhad suggested, Kata thought, glancing athim. But somehow it sounded a lot lessthreatening when Lyell said it.

Though apparently not to all of them."So what're you going to do—invite himin for tea and fruit sticks?" Adler asked."He shot at you, remember?"

"Perhaps he mistook the sound for

local fauna," Lyell shrugged. "Or else hespotted our drawn lightning rods andthought we were coming to attack him.Either way, we can't afford to leavematters as they stand." He paused, andhis face took on a thoughtful look. "Ipresume you all realize that we may beon the brink here of finding out whywe've never before run into anyintelligent species in this part of space."

"What, the old 'shy alien' hypothesisagain?" Adler grunted. But even he hadthe beginnings of a gleam in his eye. "Isuppose it's not impossible."

Lyell shifted his gaze to Kata. "You'rebeing pretty quiet, Kata. What are yourthoughts on all this?" She shook herhead. "I don't know," she admitted. "The

Robinson Crusoe theory works as wellas any other, I suppose, but there are stillholes in it you could fly the Sunraythrough. If that dart gun of our theoreticalalien is supposed to be a survivalweapon, why doesn't it carry a morelethal poison?—cyanide, for trivialexample; that'll kill most oxygen-breathers we know of. Furthermore, if hecrashed this close to us why haven't oursurveys picked up evidence of it? And ifhe hit far away, how in starnation did hefind us?"

There was a moment of silence. ThenMitch cleared his throat. "This poison—it is a real poison, isn't it?"

"I'm sure it's supposed to be, butagainst us it hardly qualifies as one,"

Lyell told him. "It affects the nervoussystem locally to the extent of causingminor and temporary numbness, but thatappears to be all it does. That's onereason I'm not especially worried aboutbeing gunned down en masse."

"I see." Mitch had a frown on his face."Have you done any tests to see how thedarts work on, say, tarsap physiology?"

Kata exchanged glances with Lyell."Unh," Lyell grunted. "I see what you'regetting at."

"I don't," Adler spoke up."On a biochemical level Palladian

life is very similar to ours," Lyellexplained, stroking his chin thoughtfully."If the darts don't bother us much, theyaren't likely to kill native animals either,

at least not quickly enough to be usefulfor hunting or defense."

"Bang goes the survival weapontheory," Mitch murmured. "Lyell, thisisn't getting us anywhere. If the drug isn'tdangerous, maybe Adler and I should goout and see if we can find our trigger-happy guest. Before he figures it out andswitches to a stronger weapon."

"You don't mind if I do my ownvolunteering, do you?" Adler snapped.

"First things first," Lyell shook hishead. "No one's going back outside untilwe have the Sunray back to monitorthings from the air. Kata, you and Mitchare to try and extract the main poisonreservoir from the second dart anddouble-check the blood analyzer's

chemical formula. Adler, I guess you canjust go about your work. As soon as thescrubber here's finished with me, I'llgive the Endurssons a call."

"If it's all the same to you," Adlersaid, "I think I'll continue watching thewindows. Even high-impact plastic canbe broken if you hit it hard enough.Mitch?"

Silently, Mitch handed over the laser.The geologist strapped it on and left theroom, and Mitch stepped oyer to thetable where the second dart lay on itsgauze pad. "Come on, Kata," he said,picking it up. "Rom will have hisstandard snit if Lyell doesn't have somehard data to give him when he calls."Mitch didn't hear the radio conversation

Lyell had with Rom: but when theEndurssons finally arrived an hour aftersunset Rom wasted no time in making hisannoyance public. "All right—let's seethese so-called poisoned needles," werehis first words as Mitch met them at thedoor.

"Sure," Mitch said, swallowing thegreeting he'd started to give. "The othersare in the biolab." Rom snorted andstrode past him. Shannon gave Mitch asmile that was half greeting, halfapology, and hurried after her husband.Suppressing a grimace, Mitch followed,glad that the conversational burdenwould be shifting from his shoulders toLyell's.

Lyell and Kata were indeed waiting in

the lab when they arrived, Adler with agood sense of timing having chosen thatmoment to be elsewhere. "Lyell," Romnodded briskly. "What's all this fuss thatyou absolutely had to drag us away fromour work over?"

Lyell flipped on the microscopeprojector and gestured to the screen. "Iwas shot with two of those darts," hetold the other without preamble. "I washoping you might have run into this kindof weapon before in your studies."

Rom stepped up to the screen, andMitch felt a smile of admiration twitch athis lip. Only Lyell would think ofdrawing the archeologist into this byappealing to his professional judgment.

"Composition?" Rom asked, adjusting

the light a fraction."An alloy of nickel, iron,

molybdenum, and manganese," Lyell toldhim. "There may be a very thin layer of alacquer coating on it, too; Adler wasn'tsure. Its main claim to fame is that it's anextremely ferromagnetic material."

"In other words, the gun that fired ituses magnetic rings instead ofcompressed gas or chemicalexplosives," Rom said, his tone implyingthe others should have figured that outlong ago. They had, actually, but Lyelldidn't bother to say so. "Seemsreasonable—neither Kata nor I heardany sound except the whistle of the dartsthemselves."

"Means a reasonably high

technology," Rom continued as if Lyellhadn't spoken. "Could have come fromthe ruins, I suppose. Have you done analloy-bond dating yet?"

"Adler couldn't get both age andcomposition from the other dart, and Iwouldn't let him have this one too."

Rom snorted. "Adler thinks you needa kilo of sample to do anything useful. Ican probably get a good approximationfrom whatever he's got left."

"Wait a second," Kata spoke up. "Areyou saying the sniper could be asurvivor from a dead civilization?"

"More likely an outcast or someoneaccidentally left behind," Shannon said,the quiet patience in her voice formingits usual contrast with the lack of that

quality in Rom's. "Or a descendant ofsuch a group. The people who builtthose ruins seem to have arrived ratherabruptly on Pallas and then have leftequally abruptly. There is no 'deadcivilization' here, just temporaryvisitors."

"Visitors?" Lyell frowned. "I got theimpression from your reports that theseruins were more elaborate than a simpleexploration team bivouac."

"They are," Rom said. "All of them sofar have shown evidence of extensivepermanent buildings—one of them evenhas a nested series of perimeter walls,which indicates periodic growth of thesettlement."

"Sounds more like a fort setup," Mitch

murmured."Doubtful," Rom shook his head. "The

walls weren't thick enough to defendagainst any real attack. Probably theywere just decorative." He peered at themagnified needle for another minute. "Igather you want me to take the Sunray uptomorrow and look for whatever's outthere shooting these things. Suppose hedoesn't want to be found?"

"We'll just have to flush him out,won't we?" Mitch said, and immediatelyregretted it as Rom sent him a look ofdisgust that could have sterilized cultureplates at twenty paces.

"I don't suppose it occurred to you thathe may not want our company," thearcheologist said icily.

"If he's used to being alone or part ofa small group we'd probably scare thehell out of him charging in on him likethat. In fact, maybe that's what startedhim shooting in the first place."

"We've been tromping all around thispart of Pallas for well over six months,apparently without bothering him." Lyellpointed out. "Why should he startshooting now if he doesn't want anyattention? If, on the other hand, he justgot here, it may be he is in need of helpor company."

"He's got a funny way of showing it,"Rom grunted. "But my original questionwas how you intended to locate him inthe first place. If you were counting ont h e Sunray's sensors to pick up the

needles or magnets, you can forget it. Aproperly designed mag-ring gun doesn'tleak very much field, even when it'sbeing fired."

"Then we'll walk around and listenfor the tarsapien enemy call," Kata putin.

"The what?""Lyell and I heard a tarsapien danger

cry just before the needles startedflying," she amplified. "At the time wethought it meant a heloderm wasscuttling around, but now I'm not sosure."

"And why would the tarsaps identifythis visitor as an enemy?" Rom snorted."They don't treat us that way."

"I only meant—"

"It's as good a working assumption asany," Lyell interjected mildly. "Thewhole tarsap community was unusuallyquiet this morning, and I've never knowneven a family of heloderms to cause areaction that widespread. Do you haveany idea yet what the people who builtthose ruins looked like?" Rom shrugged."Bipedal, certainly; probably at leastvaguely humanoid, as well. We haven'tyet located any photos or sculptures thatwould tell us for sure, but all the moresubtle indications are there." He favoredLyell with a sardonic smile. "Don'tworry, I'm sure he'll be distinguishablefrom any tarsaps in the area. He'll beholding a gun, for one thing. When doyou plan on organizing this hunt?" Lyell

winced slightly at the word hunt butdidn't comment on it. "I thought earlytomorrow morning you could take theSunray up and just see if you can pick upany traces of our visitor from above. Ifnot, Mitch, Adler, and I will go to thespot where I was shot and work outwardfrom there. Unless you have anothersuggestion?"

"No, I suppose that's as good a plan asany," Rom said. "You won't object if Ileave any details to the rest of you?—I've got some samples I want to getcatalogued. I thought not. Good night,all." Without waiting for a reply, heturned and disappeared down the hall.

Always a pleasure, Mitch thoughtsourly, but he refrained from saying it

aloud. Shannon was still in the room,and whatever he thought of Rom he didgenuinely like her. So he merely gaveher a friendly smile and strolled over towhere Kata was tapping her fingers idlyon her terminal. "Feeling any less scaredthan you were this afternoon?" he asked,pulling up a chair beside hers. She didn'tturn to face him, and her fingers haltedtheir drumming only for a moment. "Yesor no," she answered over her shoulder."I'm not as afraid of the needles as I was. . . but the rest of it just keeps gettingworse."

"You mean Rom's odd-man-outtheory? I agree it's shot full of holes—"

"Doesn't that bother you?" sheinterrupted, turning to give him a strange

look. "This isn't some nice, safetheoretical discussion about theecological function of Frensky moss.There is a real someone out there,shooting real needles for real reasons—and it seems to me that charging into thiswithout knowing what we're doing couldbe dangerous as well as plain stupid."

The intensity of her outburst startledMitch, and he glanced over to see ifLyell had heard. But the other was deepin quiet conversation with Shannon. "Ifyou feel that way," he asked Kata, "whydidn't you bring it up a few minutesago?"

She shook her head and turned awayagain. "Lyell had his mind made up—you saw that."

"But you're—" his lover "a long-timecolleague. Someone he trusts. You couldchange his mind." She snorted. " No onechanges Lyell Moffit's mind once he'sdecided on a course of action." Her facewas still turned away, and Mitchabruptly realized what she was staringat. Crouching motionlessly in one cornerof his cage, Swizzle had a preternaturalalertness about him. Occasional ripplesof muscle sent waves through his fur,and his flared nostrils were larger eventhan his unblinking eyes. "How long hashe been like that?" Mitch asked quietly.

"I noticed it when we were workingon the needle drug analysis earlier. Idon't think he's moved half a meter sincethen."

Mitch shivered. Generalizing fromone species to another was always aniffy proposition, but he'd rarely seen amore textbook example of herbivoredanger reaction. "Could he have heardthe tarsap enemy cry earlier?"

"I don't know. Actually, I'm not quitesure how to read this; he acts nervous,certainly, but he accepted his dinnerfrom me without any hesitation I coulddetect."

"In other words, it's not us he's afraidof?"

"I wouldn't even swear to that. I justdon' t know," Kata's fingertips slappedthe console one final time and came to ahalt. "Well . . . maybe it'll all proveacademic, after all. If you catch the

sniper tomorrow we should be able toput all the pieces together easilyenough."

"Maybe." Mitch glanced once more atSwizzle and then turned away. "Might beinteresting to see if his wake-up calltomorrow has any of the 'danger'overtones in it, though."

"I've already got the recorder set up."Mitch had planned to be listening

when the tarsapien cry came the nextmorning; but though he was up well inadvance of the event he wound upmissing it entirely as he walkedinnocently into the common room andstraight into a full-fledged war of words.

Lyell, it seemed, had finally run afoulof his own abundant self-confidence.

Apparently simply assuming Adler'scooperation in the morning's activities,he hadn't bothered to clear his plans withthe geologist . . . and Adler was notamused at having been volunteered forsuch clearly hazardous duty.

"I don't care," he was saying whenMitch arrived. "I'm not going out there tobe shot at on a half-hour's notice. Notwithout better protection than thesecoveralls—certainly not without a betteridea of what we're up against."

Even Lyell's temper was showingsigns of strain. "I've told you what thedarts contain—"

"And you've assured me it's notdangerous," Adler interrupted him. "AndI'm sure you're not deliberately lying to

me. But what about long-term effects ofthe residue you can't flush out? Whatabout cumulative effects? Face it, Lyell;you haven't got nearly enough answersyet."

"I presume we're open tosuggestions," Mitch said, sitting downnext to Shannon. Rom, seated alone onthe far side of the table with a look ofsour amusement on his face, seemed tobe staying out of the discussion.

"My idea's already been trampled on,thank you," Adler said, his voice frosty.Lyell shook his head wearily. "Adlerthinks we should just expand ourherbicide ring—excuse me, our cordonsanitaire—by a factor of ten or so. Keepthe sniper at a distance. Be reasonable,

Adler; even if we had the herbicide tomaintain it, we couldn't begin to clearthat much space quickly and safelyenough."

"If you say so. But I'm still not goingout there."

The impasse lasted several minuteslonger, with Lyell running through anamazing repertoire of persuasions andinducements before giving up. "All right,then," he said, standing up. "I guessMitch and I will have to do it alone. Youready, Rom?"

"Whenever you are," Rom said. "If itwould help, though, I suppose I could letAdler take the Sunray and go with youtwo myself."

You might have suggested that ten

minutes ago, Mitch thought—and wasopening his mouth to say so when Lyellbeat him to the draw with a far morediplomatic comment.

"That's very generous of you, Rom;thank you. Well, Adler?"

Adler shot an irritated glance inRom's direction; but having basicallypainted himself into a corner he hadlittle choice but to accept the offer. Lyellpretended to take it all at face value, buteven he couldn't quite carry it off, and itwas a quiet group that headed out intothe forest. The forest, too, was quiet—quieter than Mitch had ever known it. Hefelt the eerieness of it all as he, Lyell,and Rom fanned out toward the spotwhere the mysterious sniper had first

struck. Overhead, the Sunray was ahumming blue-and-gray shadow driftingabove the ginkgaps and manzanis; behindthem, unseen but ever present, Kata andShannon monitored the Lostproof andground-to-air equipment and directed thesearch. It was, Mitch thought more thanonce, almost as if he were back incollege playing the elaborate Search andStrike games that had been all the ragethen. Those had been fun . . . but in thosehe'd been facing only chalk-dye pellets,not high-velocity needles.

"Still nothing," Adler's voicemurmured from the communicatorstrapped to Mitch's shoulder.

"Computer enhancement's not gettinganything from the data, either," Kata put

in. "Lyell, I think Rom was right; thatgun's not going to show on the Sunray'ssensors."

"Well, we'll leave him up there—"Lyell broke off abruptly as a tarsapienscreech split the air off to Mitch's left."Report," Lyell said quietly.

"About thirty degrees left," Mitchwhispered toward his shoulder,squeezing the "mark" button on hisLostproof to feed its position andorientation back to Shannon's monitor.

"Directly to my right," Lyell said."Rom?"

"Straight ahead," the archeologist saidcalmly. "I guess I win."

"Stay there," Lyell ordered. "Mitchand I'll move in to flank him. Shannon . .

. ?""Got a probable location—feeding to

you." Mitch glanced at the small whitecross that had appeared on his Lostproofdisplay and headed in that direction.There was no guarantee the loudtarsapien was sitting directly on top ofthe sniper, and he didn't want to blundercarelessly into a couple of thoseneedles.

He was no more than twenty metersfrom the spot Shannon had marked whenthere was a rustle of movement in thetrees ahead. "Lyell?" he whispered."Something moving up there."

"I can see it," Rom put in. "Just atarsap."

"Okay," Mitch nodded. He took a

careful step forward, eyes scanning theundergrowth—

The needle jabbed in from almostdirectly above him, tracing a line of firedown his right shoulder-blade. With ayelp he threw himself to the side,reflexively raising his lightning rod as ifto ward off the attack. A second needlewhistled down to nick his thigh as hescrambled toward the nearest tree trunk.Dimly, he heard Lyell calling his name."In the trees!" he shouted as his brainunlocked for a second . . . and as a thirdneedle slapped into the tree beside hischeek the forest seemed to explode withnoise.

The crash of breaking branchesoverhead was the worst, giving Mitch

the momentary feeling of being caught ina wood pulverizer. A swish of a bodythrough the foliage and a glimpse of bluemetal an instant later told him what hadhappened: Adler had rammed the Sunraythrough the upper tree branches in anattempt to dislodge the sniper.Simultaneously, a flash of laser lightfiltered through the undergrowth ahead.The scramble of something among lowbranches—Rom's bellow—three morelaser flashes—

And with an unearthly screamsomething large crashed to the ground.

For a moment there was silence."Mitch?" Lyell called, his voice echoedby the communicator jammed into hisneck.

"Here," Mitch answered, struggling tohis feet. There was a rustle of branchesand Lyell appeared, an oddly tight lookon his face. "You get him?" Mitch askedas the other gave him a hand up.

"Yeah. You okay?""Couple of needles—those damn

things hurt going in. What's he looklike?" Lyell's expression tightened a bitmore. "Come and see."

The body was lying on the crushedremains of a sarcacia bush, its furmarked with the red-in-black swaths oflaser burns. Still gripped in its hand wasa sleek, jet-black pistol—gripped sotightly, in fact, that Rom was havingtrouble prying it loose. For the moment,though, Mitch had little attention to spare

for the weapon; his full and unbelievinggaze was on the creature holding it. Atarsapien.

"Got to hand it to you biologists,"Rom grunted as he straightened up, thepistol held loosely in his hand. "Whenyou goof, you do it right. Canine-levelintelligence, wasn't it? This one musthave been a particularly fast learner."

"Lyell, what's going on?" Kata's voicesaid at Mitch's shoulder.

"We got the sniper," Lyell answered,the words seeming to stick in his throat."It's—well, it seems to be a tarsap."

" What?""Yeah." Lyell shook his head-in a

gesture of bewilderment. "He must havefound the gun somewhere; in one of the

ruins, probably. Then figured out how touse it . . . somehow . . . ."

"Or else won it from a tourist in acard game," Rom put in sarcastically.Hefting the pistol, he sighted down thebarrel, a slight frown creasing hisforehead. "Don't worry—I'm sure you'llbe able to salvage your theoriessomehow."

"We'll certainly take a crack at it,"Lyell agreed, sounding more on balance."Mitch, can you travel under your ownpower?"

"Uh . . . well, my leg feels sort oftingly—"

"Never mind." Lyell stepped to hisside and offered a supporting arm."Rom, if you can carry the tarsap I can

take that weapon.""Okay." Rom raised the gun, but

halfway through the gesture hesitated andslipped it into his belt instead. "No,thanks; I can handle both." Reachingdown, he manhandled the dead tarsapienonto one shoulder and checked hisLostproof. "Let's go," he said, headingtoward home. Traveling only a bitslower, Lyell and Mitch followed.

They were halfway across theherbicide ring when the impossiblehappened; and because it wasimpossible none of them reacted duringthe precious handful of seconds thatmight have made the difference. Fromthe treetops behind them wafted down ahigh-pitched tarsapien cry . . . and even

as Lyell paused to look around theneedles began to fly.

"Run!" Rom yelled, sprinting for thesafety of the building. Mitch tried tofollow, but Lyell had been caughtflatfooted and it cost the two of themanother second to get their feet movingin synch. Mitch bit down hard as afamiliar sting scratched across his arm.Lyell seemed to falter, nearly pitchingthem headlong onto the ground; shiftinghis grip, Mitch managed more by luckthan anything else to take Lyell's weightand keep them moving. The last foursteps seemed to take forever . . . andthen they were through the open door,slamming into Rom as the archeologistwas starting back out. They fell together

in a heap, another couple of needlesricocheting from the floor and wallsbefore Mitch managed to get a foot freeand kick the door closed.

It wasn't until he and Rom got to theirfeet that they discovered why Lyell wasbeing so quiet. The work on Lyell wasslow, nerve-wracking, and frustrating,and by the time Kata rememberedMitch's injuries she already felt as ifshe'd been run backwards through afaulty garbage recycler. But despite thefact he'd been left lying on the diningtable for over an hour there was noanger or impatience in his face orposture when she finally looked in onhim. "How are you feeling?" she asked,hoping the deadness within her didn't

come across as disinterest."I'm all right," he said quietly. "You

can leave the needles in until later ifyou're still busy." She shook her head. "Ican't do anything more for Lyell nowexcept let him sleep. Where were youhit?"

"Right scapula somewhere and leftthigh rectus muscle, if I'm rememberingmy anatomy classes properly." Hepaused. "How is he?"

Something in his voice made her takeanother look at his face, and it finallypenetrated her own cloud of fear andanxiety how hard he was taking this."He's not doing too badly," she told him."Still unconscious, but I'd have sedatedhim anyway. I think he'll pull through

okay.""Shannon told me there's a needle

lodged in the heart muscle.""Near, but not actually in it," Kata

corrected, silently thanking heaven forsmall favors. "Unless it migrates itshould be all right to leave it there."

He twisted his head up to look at her."You're not going to take it out?" Katashook her head tiredly. "No, and I'vealready gone six rounds with Adler overthe decision, so please don't you start.The needle went in between two ribs,just missing the spine, and there's simplyno way I can get at it with the non-specialized equipment we've got here."She bit her lip as she applied a freshlayer of anesthetic to Mitch's shoulder

wound. "Not to mention my own lack ofskill, of course."

"Yeah."She worked in silence for a moment,

the part of her mind not actuallyinvolved with the operation trying tocome up with words that would soundconvincing. But Lyell was the one withthe silver tongue, and eventually shegave up the effort. "It's not your fault,you know," she told Mitch.

"Isn't it? Rom made it in without ascratch . . . but he wasn't being sloweddown by someone with only one and ahalf legs. Lyell could have let go of meand saved himself."

"In that case, it was his decision andagain wasn't your fault." Kata shrugged.

"Anyway, who's to say what would havehappened if he'd let go? You're the onewho got him inside, remember. Withoutyou the tarsapien might have had time toput a dozen more shots into him."

"Maybe." Mitch sighed. "Kata . . .what the hell is going on here? Tarsapswith guns, shooting at us—it's likesomething out of a plot for City of Night.You know—the old Natives Rising ToThrow Off The Human Conquerorsgimmick. Could the tarsaps somehowhave hidden a technological civilizationfrom us?"

"No." There was a lot about this thatKata didn't understand, but of that onething she was certain.

"Remember the Bateson neural

dexterity index? The tarsapiens arebiologically incapable of inventingsomething as advanced as a needle gun."

"But that conclusion assumes Swizzleis a typical example. Is there any chancehe's the tarsap equivalent of an imbecile,deliberately planted on us to skew ourdata?"

"You forget I've got disks full of dataon tarsapiens in the wild as well.Anyway, if they were so intelligent thatthey could fool us that thoroughly, whytip their hand now?"

"I don't know." Mitch hissed betweenhis teeth as Kata began easing the needleback along its original path. "But theoption is to believe that they justhappened to find at least two working

needle guns in some multi-hundred-year-old ruin and that the tarsaps that foundthem both traveled several hundredkilometers to this same spot and thatthey only shoot humans and not eachother with them." He ran out of breathand fell silent.

Kata withdrew the needle and laid itin a culture plate. For future analysis, adetached part of her mind said. "Itdoesn't make much sense either way,does it?" she admitted, moving down towork on Mitch's leg. "Well . . . Rom andAdler are looking at the gun now. Maybethey'll come up with a better theory. Ijust wish we had better deep-probeequipment for them to use."

"I wish we had a way to call out-

system for help," Mitch retorted.Grimacing, Kata nodded. If wishes werehorses . . . .

It took another half hour to remove thesecond needle and clean the wounds,and afterwards she helped Mitch to thebio lab for a session with the bloodscrubber. She had finished theconnections and was thinking about lyingdown for a while herself when Lyellwoke up.

"I gather I took a fall," he said as Katacame over to the cot they'd set up forhim.

"Of a sort," she said, checking thesensor readings and trying to keep hervoice reasonably cheerful.

"Tried running away from a needle

that was running faster.""So that part wasn't a dream," he

murmured. "I was almost sure . . . ." Heclosed his eyes briefly and seemed tocome a bit more awake. "Did the tarsapwe killed get lost?"

"No, we've got both it and the gun,"Kata said.

"We need to do an autopsy on it,"Lyell said. "Find out why it wasdifferent. Why it shot at us."

"It's probably not—" Kata clampedher teeth firmly across the sentence.Already Lyell's eyelids were drooping;now was not the time to attempt arational discussion with him. "You justsleep and get yourself well," she saidinstead. "We can handle things until

you're back on your feet again.""All right," Lyell's eyes were closed

now, but with an obvious effort heforced them open a crack.

"Kata? Until I'm better . . . you're incharge of the expedition."

"Me? But—""Please. You're the only one who can

do it."She gritted her teeth; but the important

thing was that Lyell should get to sleepwithout any added burdens on mind orbody. "All right, Lyell, I'll do my best tokeep everything running smoothly."

"Thank you." Lyell's eyes closed, andwith a sigh he settled back to sleep. Fora moment she watched the sensors,wishing she knew what normal readings

ought to be in this kind of situation. Weshouldn't have let him go out there, shethought miserably. We should havemade him stay here, or at least up inthe Sunray. No matter how safe theneedles seemed we should have madesure our only doctor was as protectedas possible. But with all the advances ofmodern technology no one had yet comeup with a way to make second-hindsightprofitable. Putting the chain of what-ifsfrom her mind, Kata went to Lyell's labtable and the dead tarsapien lying there.Her nap would just have to wait untilafter the autopsy. It was a somber groupthat assembled in the bio lab thatafternoon—an atmosphere undoubtedlynot helped by the presence of Lyell lying

unconscious on his cot against the wall.Kata didn't care much for the constantreminder of their danger either, but shewas becoming increasingly reluctant toleave him alone.

"To start," she said, looking aroundthe circle of people clustered around herlab table, "I'd like to get the tarsapienhimself out of the way. The preliminaryautopsy shows nothing especially out ofthe ordinary about him: no extra brainmass, no anomalies in coloration ororgan size—in short, no indicationwhatsoever that he's a member of atheoretically superior sub-species oftarsapien. The computer's doing adetailed biochemical analysis now, but Ibelieve it's safe to say he did not make

the gun himself." Rom snorted. "I toldyou that hours ago." Besides him,Shannon shifted slightly in her chair, butsaid nothing.

"It's nice to have proof, though,"Mitch murmured. There was still ahaunted look about his eyes, Kata noteduneasily: mute testimony to the fact thathe still felt some responsibility forLyell's injury. "How far did you two getwith the pistol?" he added.

"Depends on what you want," Romsaid. He glanced at Adler, as ifexpecting the other to say something. Butthe geologist was staring in the directionof Lyell's cot, his mind obviously light-years away, and with a quiet snort Rompulled the black weapon from his belt

and held it up. "Length, about fifteencentimeters, main body about four bythree, grip about six long and an ovalcross-section about twelve centimetersin circumference. The front half of themain body contains a series of seventyrings that, judging by their reaction toapplied magnetic fields, are room-tempsuperconductors." Abruptly, Katanoticed that the pistol, which had startedout being held by the fingertips of Rom'sright hand, had slipped imperceptiblyinto a cozy position in the archeologist'spalm. There was nothing overtly hostileabout that—certainly Rom wasn'tpointing the thing at anyone—butsomething about the action neverthelesssent a quiet shiver through her body.

"Rom, can we put it under the fluoroscanhere?" she cut into his monologue. "Seewhat it looks like inside?" He glanceddown at the gun in his hand, almost as ifseeing it for the first time. "No need," hetold Kata, lowering the gun to his lap butmaintaining his grip on it. "It's all on thecomputer—Datapack ALP." Feelingvaguely disturbed, Kata reached to herterminal and accessed the proper disk. Amoment later, she had an x-ray view ofthe pistol on the screen.

Mitch whistled softly. "Crowded inthere, isn't it? What is all that stuff?"

"Looks like some sort of relativelysimple sensor at the tip of the barrel,probably part of the firing mechanism,"Rom said. "The stuff behind the rings is

more electronics and what seems to be asmall powerpack. That narrow thingaround the inside edge of the grip is areservoir of some liquid, probably alubricant. The rectangular block takingup the rest of the grip—" he hesitated—"appears to be the ammunition."

"The whole thing?" Kata asked, hereyes and brain trying to reconcile thesizes of the tiny needles she'd becomefar too familiar with and the solid-looking mass on the computer screen."There must be—oh, thousands ofneedles in there."

"Something under nine thousand,actually," Rom said. "The reservoir alsoappears to be about half empty."

Mitch was the first to break the

silence. "An eighteen thousand shotclip? What were they fighting, anyway,the Hundred Years' War?"

"How should I know?" Rom retorted."Maybe it was just their version of thedisposable flashlight—a sealed unit thatyou throw away when it's empty."

"Sealed?" Kata frowned. "You meanyou can't figure out how to open it?"

"If I'd meant that I would have saidthat," Rom said, his voice heavy withscorn. "I mean there is no way to open it.Not unless you want to ruin part of themechanism getting in." Clamping hermouth firmly shut over her irritation,Kata looked back at the image on thecomputer screen. "I think we're going tohave to risk it," she said. "There's only

so much we can learn from indirectstudy—"

"Well, forget it," Rom interrupted. "Iknow you biologists are used to cuttingup everything in sight, but you're nottaking your scalpels to my gun."

" Your gun?" Kata asked. "Sincewhen?"

"Since when do you give ordersaround here?" Rom countered.

"Since Lyell put her in charge thismorning," Mitch spoke up.

"He did that?" Shannon asked,frowning. "Why?"

"Well, obviously he's not in any shapeto run things himself," Mitch shrugged."He woke up long enough to order anautopsy on the tarsap and then told Kata

to run things until he was better.""Ridiculous," Rom snorted. "Lyell

must've been delirious.""Now you're being ridiculous—""Enough," Kata interrupted. Mitch had

a lower threshold of irritation than evenAdler, and the last thing they needed wasa knock-down argument about who gotthe dubious honor of Lyell's hot seat. "Incase you've all forgotten, there's atarsapien out there with a gun—one ofthose guns, Rom. Wherever he got it, weneed to know everything we can aboutthe thing if we're going to come up witha defense." Rom's face was settling inalong well-defined frown lines; butbefore he could reply Shannon spoke up."Surely there are other tests and studies

we can do before we have to riskdamaging the gun," she said. "After all,the immediate problem seems to me tobe learning how to locate or defendagainst the weapon, not necessarilylearning all the details of how it works."Kata hesitated . . . but it wouldn't costthem more than a little time, and if theycould postpone this fight until Lyell wasback in charge the final decision wouldprobably be reached with less emotionalbloodshed. "All right," she said with asigh. "Rom, why don't you take the gunback to your lab and—oh—set it up inthe NMR chamber. We could havedinner while the thing's getting a goodcomposition profile."

"I know what to do," Rom snorted,

getting to his feet and starting for thedoor. There he paused, staring for amoment at the alien weapon still grippedin his hand. "Don't hold dinner for me—Imay just wait until the analysis isfinished."

He left, and Kata felt a prickling ofthe hairs of her neck. It was the sort ofparting shot they all expected from aloner like Rom . . . but there'd beensomething about the way he'd looked atthat pistol that bothered her. You'regetting hypersensitive, she told herselffi rmly. Hypersensitive and maybe alittle paranoid.

Beside her, Mitch cleared his throat."Shannon, is he okay?" he asked quietly."I mean . . . he seems a little . . . ."

"Preoccupied?" Shannon suggested.Her eyes were on the empty doorwayand there was a slight furrow betweenher eyebrows. "Yes. He does, doesn'the."

So I'm not imagining things, Katathought. "Why did he refer to the gun ashis?" she asked Shannon. "Because it'slike the other artifacts you're alwaysdigging up?"

"Archeologists don't become attachedto the things they find," Shannon shookher head. "We nearly always wind upgiving them to someone else. And Rom'salways been even less possessive thanmost of the others I know."

"He's sure making up for it now,"Adler spoke up.

Kata turned to him in some surprise—she'd almost forgotten he was there—and found him still gazing at theunconscious Lyell. "What do you mean?"

"I mean he wouldn't so much as let metouch that damn gun while we wereworking on it," the geologist said. " Heheld it under the fluoroscan, he took allthe caliper measurements, he moved itbetween machines when necessary. Allhe'd let me do is punch in the data."

"Um." That did seem excessive, Katathought. Still, Rom had never been at hisbest in group situations. "Well . . . Romdoesn't ask much of the rest of us. Isuppose we can indulge him this once."

"He still shouldn't carry that gunaround like a personal sidearm,"

Shannon said, standing up. "I'll try to getthat through to him, at least. Oh, andplease don't wait for me, either—I'llmake a private supper for Rom and meafter you've eaten." With her usual half-apologetic smile she left.

"Going to be a small group fordinner," Kata remarked, trying for a lighttone. "I don't know about you two, butI'm famished."

"Yeah." Mitch got up from his seat,his eyes flicking once to Lyell and then—Kata thought— guiltily away. "Myturn to cook, I suppose. I've certainlyhad the easiest day of everyone."

"Adler?" Kata asked, turning to thegeologist. "You coming?"

"In a while," the other answered. "I'm

not really hungry yet." Kata followed hisline of sight. "There's nothing you can dofor him right now," she said. "I'veprogrammed the sensors to alert me incase of any change."

"I know. I just want to sit here awhile." He hesitated. "I'm not afraid ofdying, Kata—I'm not, really. I just don'twant to die now, with my career andprofessional reputation as low as theyare. I—well, I'm sure you didn't know it,but the main reason I came to Pallas wasthat so many of Lyell's companions havereturned from these trips to publishoutstanding papers. I rather hoped someof that luck would rub off on me."

"I see," Kata said. The revelationwasn't exactly news to her—Lyell had

read Adler's motives correctly rightfrom the start—but there wasn't anypoint in telling him that. "Okay. Call meif he wakes up; otherwise, I'll be back inan hour."

The dinner Mitch fixed for them wasquick, simple, and under othercircumstances would probably havetasted quite good. But with all the strainsand uncertainties of the situation buzzingaround her like a swarm of sweat gnatsthe food went down like so muchuntextured protein supplement. Midwaythrough the meal Shannon unexpectedlyappeared, and though she acted civilenough the single meal she heated andsat down to eat spoke volumes abouthow her talk with Rom had gone. First

Adler goes all quivery, Kata thoughtglumly, and now Rom and Shannon arehaving some kind of polemic. Pleaseget well quick, Lyell—I can't hang ontothis tiger much longer. But that hopeproved cruelly short-lived. Four hourslater the medsensor alarms signalledLyell's lapse into a coma, and despiteKata's best efforts his condition steadilyworsened. Two hours later, he wasdead.

The morning sun was filtering throughthe trees by the time Kata called themtogether again. "The best guess I canmake is that the drug in the needleinterfered with Lyell's autonomicnervous system enough to cause aslowdown of his heart," she told them

quietly. "I don't know whether the drugalso caused the subsequent metabolismdrop or whether that was a reaction tothe slower heartbeat—" She caught herbreath as her voice began to tremble,and Mitch winced in sympathetic pain.To have had to perform even abiochemical autopsy on a man she'dloved; wondering probably the wholetime whether different treatment couldhave saved his life . . . . "Whichever,"she continued, once again under control,

"he seems to have just drifted off . . .and died."

"So your 'harmless' poison turns outnot so harmless after all," Adler saidheavily.

"We never said it was harmless; only

that—" Kata waved a weary hand. "Oh,never mind. Rom?

What more have you found out aboutthe weapon?"

Kata had been up most of the night,handling what was undoubtedly the mostemotionally draining situation of her life,and she looked it. And yet, as Mitchstudied Rom, he decided thearcheologist looked even worse. Hisface was drawn and pale, as if he'dspent a month with a debilitating illness,and even in the cool of the morning therewas a sheen of perspiration on hisforehead. He hadn't bothered to shave,and his eyes seemed unable to shift fromtheir steady gaze at the floor. But hisvoice was clear enough, and the hand

that gripped the alien pistol in his lapshowed no signs of infirmity. "Nothingvery useful," he said, staring at a spotnear Kata's feet. "I've got the feedmechanism figured out—an unorthodoxbut straightforward scheme that seemstotally jam-proof. I also took a sliver ofmetal from the underside of the barrel,and it looks like the gun's twenty to fiftyyears older than any of the ruins we'vestudied."

"It is?" Shannon frowned, and Mitchfelt his eyebrows lift at her surprise.Freezing Adler out of the work had beenpar for the course with Rom; butShannon's reaction meant he'd kept herout as well, and that was well-nighunheard of. Mitch glanced at Kata, saw

the same thought flicker briefly acrossher face.

"Yes," Rom said, "and it sort ofblows the theory that that's where thetarsaps found them."

"Unless the settlers brought twenty-year-old guns with them," Katasuggested. Rom snorted. "I thought we'destablished these things were useless forhunting local animals. I suppose theybrought a bunch of semi-infiniterepeaters to use on each other?" Kataflushed. "Maybe the different settlementsweren't put up by the same people. Youever think of that?"

For a second Rom's eyes locked withKata's and Mitch braced for anexplosion. But apparently Rom wasn't in

the mood. "Yeah, I've thought of that," hesaid, his gaze slipping to the floor again."But the building styles are virtuallyidentical. Besides, the weapons don'tseem very practical for warfare."

"They kill well enough," Adlermurmured.

Kata seemed to wince, and Mitchhastened to step in. "What happened toLyell was a fluke," he pointed out."Anyway, there are other reasons Rom'sprobably right. Those needles havepractically no stopping power, andthey'd be useless against any kind ofbody armor. The gun's designed morelike a child's toy than like a weapon fora trained soldier."

"Or like a test for civilization,

perhaps," Shannon said.All eyes turned to her. "What do you

mean?" Mitch asked."I've been thinking over the same

questions lately," she said, her gazeflickering around and coming to rest onthe gun in her husband's hand. "Supposeyou came upon a planet like Pallas andwanted to see how stable or adaptablethe tarsap social structure was. One wayyou might do that would be to give agroup of them superior tools or weaponsand observe what happens."

"Shades of Satan in the garden," Mitchsaid. "What a rotten trick to play on aspecies."

"Is it?" Rom retorted. "Is it anydifferent really than netting Swizzle and

hauling him here to perform in a maze?You should know by now that biologistsare always playing God with the thingsthey find." Mitch clamped his teethtogether and counted to ten; but before hereached it Kata returned his earlier favorand took back the conversational ball."You're suggesting, then," she said toShannon, "that when it came time tocollect the guns and leave they missed acouple?"

"Or else didn't bother to collect themat all," Shannon shrugged. "Mitch toldme earlier that you'd never found atarsap with needles in him, so maybethey never learned to shoot each other."

"Which again leaves us the questionof why they shoot at us," Mitch reminded

her."Maybe they just don't like people,"

Rom murmured. "I can sure understandthat." He looked up abruptly, and for along second the gun in his hand waveredlike a snake unsure of its target. Mitchcaught his breath, heard Kata do thesame . . . and Rom stood up, jamming thegun back into his belt. "I need some air,"he said and strode out of the room. Evenbefore he was out of sight, he wasfumbling the pistol back into his hand.

Carefully, Mitch let out the breath he'dbeen holding. "Is it my imagination, orwas he really thinking about opening upwith that thing?"

"He was." Adler's face was a dirtywhite, his preoccupation with Lyell's

death momentarily pushed into thebackground. "And if he did he wouldhave started with me. He doesn't like me—you all know that."

"Rom wouldn't do a thing like that,"Shannon said. But her voice lackedconviction, and her face was almost aspale as Adler's. "He's not—I mean, he'snot very sociable, but . . . did any of yousee his face right then?"

The others shook their heads. "I waswatching the gun," Mitch said. "Why?"

"He looked . . . confused, sort of. Orlike he was in pain." Shannon looked atKata. "I think he's coming down withsomething, Kata. I know you and Lyellsaid that shouldn't happen, but with theway he's acting and the way he looks—"

She waved a hand helplessly. "I justthink he's ill." Kata nodded grimly. "Hesure looks like someone with untreatedintestinal flu," she agreed. "And it's notcompletely impossible for one of us tocatch something here; the differentsurface protein cues keep the localbacteria and viruses from entrenchingthemselves into our systems, but theDNA and RNA structures are similarenough for a rogue plasmid or somethingto conceivably make trouble." Shelooked at the doorway. "I'd better try andtalk him into an examination." But Romdidn't like Kata much; and with theshorter fuse this illness seemed to havegiven him . . . .

"I'll go," Mitch said, getting quickly to

his feet."You sure?" Kata asked, her voice a

mixture of relief and guilty concern."Sure. Rom doesn't seem as angry at

botanists this semester as he is atbiologists. Anyway, I can always remindhim I supported one of his arguments afew minutes ago. You want a fullmedcheck?"

"If you can get it," Kata said. "Butdon't push too hard."

"No kidding." Wondering brieflyabout the stupid things done in the nameof chivalry, Mitch went in search ofRom.

He found the other, predictablyenough, in the archeology lab, staring outthe window and ignoring the bits and

pieces of ancient rubble laid out aroundthe room. "Mind if I come in?" he askedfrom the doorway.

Rom half turned, then resumed hisoutward gaze. "Don't touch anything," hesaid shortly. Swallowing, Mitch steppedinside and closed the door. "How areyou feeling?" he asked casually, movingcarefully toward the other.

"Why?""To be honest, you look like you're

coming down with something and we'reworried about you." Rom snorted."Afraid I'll pass it on to you?"

"Not especially," Mitch said,determined not to let the other get to him."We're more afraid of what it might doto you."

"Oh, come on—none of you careswhat happens to me."

"Not even Shannon? She's the onewho suggested—"

"Shannon can go swim an ocean withthe rest of you," Rom snapped. Surprisetangled Mitch's tongue, cutting off therest of his sentence. As uncaring as Romwas about everyone else's sensitivities,Shannon had always before beenexempted from the verbal abuse. To hearthat immunity crumbling was in a waymore disquieting even than the other'sfixation with the alien weapon.

And Rom knew it. "Bothers you, doesit?" he said as Mitch was still trying tofind something to say.

"Shows you've never tried marriage

yourself. Half the time you'd be betteroff rooming with your worst enemy. Atleast then you'd know exactly where youstand."

If things are that bad . . . ? Mitchwondered. No. They've just had a fight,that's all. That and/or this illness."Deep down you know better than that,"he said, hoping it didn't sound as trite toRom as it did to him. "We care aboutyou—all of us—and Shannon most ofall."

"Deep down," Rom countered softly,"you're all my enemies. Tell me, do youbelieve in ghosts?" The verbalblockbusters were coming too fast. "I . .. don't know," he managed. "Do you?"

"Not really. But I think there are

ghosts on Pallas. I can . . . I can feelthem, almost. Hear them, too."

Oh, terrific. "What do they say?" heasked, choosing the safest response hecould think of.

"They tell me I'm in danger." Rom'svoice was calm, almost as if he werereciting from a stone tablet he'd dug up."There are enemies here, enemies I haveto try and fight. To drive away. We didthat once, a long time ago."

"We?" The word slipped out beforeMitch could stop it.

"I mean they," Rom replied. "They.The abandoned ruins are proof of that, Ithink. Someone tried to settle here andthe ones with the guns drove them off."

Mitch's mouth was beginning to feel

dry. "That's not what you were sayingabout the ruins before."

"I didn't know about the guns before,did I?" Rom retorted with a touch of hisold acerbity.

"Anyway, it's obvious now.""Not to me." This whole line of

conversation was becoming more than alittle creepy, but somehow Mitch had thefeeling he'd better stick with it as long ashe could. "You said the people who builtthe settlements were gone, but then youalso said they were still here."

"No. I said there were enemies here.Not the same ones that were here before. . . well, sort of the same . . . no . . . ."Rom trailed off, and for a long minutestared out the window in silence. "I

know who they are," he murmured atlast, almost inaudibly. "If necessary . . .." He shook suddenly, like a dogthrowing off bathwater. "So what didyou want, anyway?" he asked.

"Uh . . . ." It took Mitch a second toremember. "I think it'd be a good idea torun a quick medcheck on you. In caseyou have picked up some bug."

"Shannon's idea, right?""Sort of a group consensus, actually,"

Mitch told him, wondering if he shouldbe lying about such things. Rom'spersonality was shifting too rapidly forMitch's meager knowledge ofpsychology to keep up with. "We allcare about you—"

"Yeah, sure. All right; if it'll get you

all off my back—" Hauling himself outof his chair, Rom swung to face Mitch . .. and froze.

For that first, awful instant Mitchthought the most horrible creatures fromall the City of Night shows he'd everseen had silently lined up behind him.But Rom's eyes were locked squarely onMitch's face; and the other's look ofhorror, hatred, and fear was directedsquarely toward him. Peripherally, hesaw the gun in Rom's hand snap up intofiring position, but for once even thatcouldn't distract his attention. Eyes fixedon Rom's, unable to move and knowingit would be useless anyway, he waitedwith tensed stomach muscles for theneedles to cut into him.

They never did. Slowly, almostunwillingly, Rom turned his head; and ashis gaze broke from Mitch's face hisbody seemed to sag. "No," he growledas Mitch shook off his own paralysis andtook a step forward. "I'm all right—don'ttouch me. Go ahead; I'll follow you tothe bio lab." With that pistol trained atmy back . . . . But Rom had already hadample opportunity to gun him down.Swallowing painfully, Mitch turned andheaded toward the door.

His original hope— was that reallyonly five minutes ago?—had been thatKata and the others would clear out ofthe lab before he and Rom arrived.Now, after all that had happened, hehoped fervently that Kata, at least,

would still be there. The blood/tissueanalyzer, poor cousin to the Diagnizermachines in common use these days, waseasy enough to set up for a medcheck . . .but adjusting it to administer medicationtook more knowledge than Mitchpossessed.

But Kata hadn't been around to seeRom's latest reaction . . . and the bio labwas thus indeed deserted when theyarrived.

The analyzer took ten minutes tocollect its data, and it was among thelongest ten-minute blocks Mitch hadever lived through. Rom wascooperative enough—almost docile, infact—as Mitch got him into the chair andhooked up the twin armbands. But the

other's carefully averted eyes andrestless fingering of the alien pistol werecontinual reminders of the emotionsbubbling a millimeter beneath thesurface. Twice during that time Mitchreached silently for the keyboard,prepared to gamble that he could locatea strong enough sedative among themachine's pharmaceuticals and floodRom's system with it before the othercould figure out what was happening andriddle him with needles. But both timeshe withdrew his hand, letting it curl intoan impotent fist at his side. Fastsedatives were generally dangerous onesas well, and there was no guaranteewhatsoever that Kata would be able toneutralize that kind of overdose before it

proved fatal.And so he watched silently as the

machine finished its job, then helpedRom off with the armbands. And then,because he couldn't think of any way tostop him, he let the other leave. It wasearly evening when Kata finally pushedher chair back from her lab table andrubbed her eyes. "That's it," she toldMitch. "I'm out of ideas on what to trynext." Mitch nodded; he'd spent most ofthe day looking over her shoulder as sheran her tests, and he likewise saw thestudy at a dead end. The nucleic acidanomalies in Rom's system had shownup quickly enough, but tracking downany likely carrier—or even pinpointingthe foreign molecules themselves—had

proved impossible. "You're sure we'renot dealing with a hitherto quiescentTerrestrial virus or something?"

"Positive—the analyzer would havepicked that up right away. No, there'ssomething new in there .

. . and the crazy thing is it acts like itjust dropped out of the sky into hisbloodstream. No broken virus fragments,no plasmids or plasmid hosts—nothing."

"Could he have inhaled something?"Mitch asked, though he was pretty surehe knew the answer.

"There's no way a naked nucleic acidcould survive long enough in anunprotected environment," she said,confirming his guess.

"How about dug into a crevice or

something in the gun?""It'd still have to get through his skin."

She frowned. "Maybe we should checkhis hands for cuts or scrapes."

"I'd recommend waiting until he'sasleep tonight," Mitch said, grimacing atthe memory of their last encounter thatmorning. "You still haven't told me whatyou're going to do with him, by the way."

"You mean sedate him or not?" Katashook her head wearily. "Mitch, I knowyou're not given to flights of fancy andall, but you have to understand that Ican't do something like that on the basisof a single subjective feeling that Rom'ssomehow becoming dangerous. If I canget something— anything

—objective from this machine then

maybe we can risk it. But otherwise—"She waved her hands helplessly.

Mitch nodded, tight-lipped, andstayed for a moment out the lab'swindow. The sun had set within the pastfew minutes, and the forest beyond theirherbicide ring was darkening rapidlyagainst the blue sky above. "Whatever'swrong with Rom," he said, "we stillaren't any closer to solving our originalproblem. You given any thought to that?"

"The armed tarsapiens?" She sighed."Yes, but you couldn't tell from theresults. Every idea I've come up with sofar has had one or more flaws in it. Wehaven't got anything that would makerealistic body armor, we don't knowenough about tarsapien physiology to

come up with a safe repellent, and we'vealready proved we can't locate the gunsthemselves from any distance. I guesswe're just going to have to hole up hereuntil the ship comes back, dashing out tothe sheds for food as we need it andletting everything else slide."

"And hope the tarsaps with the gunsaren't fast enough on the uptake to pickus off each time we run outside." Heshook his head. "I don't know, though.Three months cooped up here—we'll beat each other's throats within a week."

"Especially without Lyell here tosmooth the ruffled feathers," Katamurmured. He looked at her closely; butshe wasn't, as he'd expected, on theverge of tears. Holding up well, he

thought. Unless this is going to hit heras a delayed reaction. Behind him thedoor opened, and he turned as Shannonstepped into the lab. "Have you seenRom anywhere?" she asked, her voicetight.

"Not since the medcheck thismorning," Mitch said. "What's thematter?"

"I can't find him," she said, her eyesdarting around as if he might havesomehow sneaked in without theirknowledge. "I've been through the entirebuilding and I simply can't find him."

"That's ridiculous," Mitch said . . . buteven as he spoke that unearthly look ofRom's floated back up from his memory."Have you tried calling him?" he asked,

trying to keep his sudden chill fromshowing up in his voice.

"He left his comm on our bed,"Shannon said. "And his Lostproof, too."

"He's gone outside." It wasn't whatMitch had planned to say, but suddenlyall of it clicked together in some recessof his mind and the words simply forcedtheir way out. "He's taken the gun to gofight the

'enemies.' Come on, Kata—we've gotto get him back inside."

"Wait a minute," Shannon said,grabbing at Mitch's arm as he and Kataheaded for the door. "What enemies?What's going on?"

"I'll explain later," Kata told her."Right now we've got to act fast. The

lasers are locked up in the—wait asecond." She raised her communicator,punched a button. "Adler, this is Kata.Are you still carrying one of the lasers? .. . Good. Meet us at the outside doorright away." Mitch half expected to seeRom lying face-down halfway across theherbicide ring, but that fear at leastwasn't realized. Unless he's on the farside of one of the sheds, he grimaced,studying as much of the forest as hecould see through the small window.And there's only one way to find out."Adler!" he shouted over his shoulder."Hurry it up!"

"What do you see?" Kata demanded,trying to squeeze in for a look.

"Nothing—but that doesn't mean

much," he told her shortly. "I'm going togo out and see if I can find him. Adler!—there you are," he added as thegeologist puffed into sight behindShannon. "I'm going out. Stand here inthe doorway, and if I yell start shootinginto the trees. High into the trees—don'tforget I'll be out there, too."

"What? Wait a minute—""Just do it." Wondering whether he

was being heroic or just stupid, Mitcheased the door open and slipped outside—

And was barely two paces away fromthe building when the needles beganwhining all around him. The smart move,he quickly realized, would have been tobeat a hasty retreat; but momentum and

surprise kept him moving forward, andseconds later he was flat up against theclosest shed, gulping air and waitingwith itchy skin for the needles to findtheir mark.

But, surprisingly, they didn't. For afew more seconds the hail of impactsagainst his shelter continued, thenceased. Behind him, he could hear a sortof muffled confusion at the doorway, butno laser flashes lit up the dusk. "Rom?"Mitch called. "Rom, can you hear me?You're in danger out here—you've got tocome back in." He paused, listening, buthis bellow had silenced even theanimals in the area. Already too faraway to hear? he wondered tensely. Ordid the tarsaps already get him?

"Rom!" he shouted, louder this time.Would he have headed for one of theruins? And if so, which?

We'll have to take the Sunray up, tryto spot him—

"You'll never get me, Drzewicki!"The reply would have made Mitch

jump if he hadn't been pressed so hardagainst the shed. Rom's voice was firmand clear, with nothing of an injured manabout it . . . and it came from no morethan fifteen meters away. "Go away orI'll kill you. I mean it!"

Mitch licked his lips without obviouseffect. "Rom, I want to help you," hecalled. Out of the corner of his eye hesaw the muzzle of Adler's laser pokecautiously around the doorway. Not

now, you idiot, he thought furiously; butthere was nothing he could do but try andhold Rom's attention. "Well help youhunt down the enemies," he improvisedrapidly. "You're right, they're still outthere—" A clatter of needles on metalcut him off, and when he glanced aroundthe laser had vanished back inside. "Youmust really think I'm a fool," Romsnarled. "You don't think I can recognizeenemies when I see them? I'm wise toyou now, Drzewicki—you won't fool meagain." This was starting to get sticky."Rom, no one here's trying to fool you,but if you want me to go back inside I'lldo so. Just hold your fire, okay?" Hepaused. "Okay?"

"Why?—so you can plot against me?"

Rom answered, punctuating his wordswith a few more shots. The ricochetsseemed to be changing direction, Mitchnoticed uneasily. Was Rom working hisway around the circle to a point wherehe could get a clear shot?

The unexpected beep of hiscommunicator made him start. Movingas little as possible, he snared theinstrument. "What?" he whispered.

"Get ready to move," Kata's voicesaid tensely. "I'm going to throw a flareout, try and dazzle him. When I do, makefor the door. Got it?"

"Yeah. Hurry it up—he's getting readyto nail me to the shed." His answer wasa faint creak of hinges; and with thesputter of burning magnesium the

clearing was abruptly bathed in blue-white light. Shoving off the shed wall,Mitch threw himself into a desperatesprint toward the gaping door. A wildspray of needles spattered all aroundhim, but none of them connected, andwith one final surge he hurled himselfthrough the shadowy rectangle and intoKata's waiting arms. Someone slammedthe door behind him; and for the moment,at least, he was safe.

"Mitch, what's happening out there?"Shannon asked as he and Kata regainedtheir balance. "Did you remind him thereare tarsaps with guns on the loose?"

"The tarsaps are welcome to him,"Mitch panted. "I'm sorry; I didn't meanthat—but it was Rom, not any tarsap,

who was shooting at me. He's gone crazy—thinks we're his enemies." He lookedat Kata. "Could you hear what he wassaying?"

"I got most of it," she nodded grimly."I'm sorry Mitch; I should have listenedwhen you first told me about him."

"There wasn't much we could havedone even then—" Mitch broke off andtook a long step backwards, interceptingShannon as she started for the door."Hold it; you're not going out there."

"Get out of my way," Shannon said.Her voice, no louder than a whisper, hada touch of hysteria building at its edge."He's my husband—I've got to helphim."

"You can't do anything for him now,"

Kata told her firmly, stepping to Mitch'sside. "We have to figure out what'shappened before we can help him."

"What do you mean, what'shappened? He's ill, that's what, and wehave to cure him." Abruptly, Shannonpushed, sending Mitch staggering back."Let me go to him—I'll get him backinside."

"No!" For Mitch it was a tossupwhether Shannon going out or Romcoming in would be a greater disaster;but for now, at least, both would beaverted. Even as Shannon tried to pushpast Kata, Adler reached from behind topinion the archeologist's arms. For amoment she thrashed in his grip; but asKata and Mitch moved in to assist she

abruptly gave up and stood quietly, tearswelling up in her eyes.

"Don't you understand?" she halfdemanded, half pleaded. "He needs me."

"Come on, Shannon," Kata said,taking her arm and walking her down thehall toward the bio lab.

"Let me get you something to calm youdown. You're not helping Rom like this."They disappeared around the curve, andAdler turned haunted eyes on Mitch."What the hell's happening here,anyway?"

"You know about as much as I do,"Mitch answered shortly, stooping tostudy the door's latch mechanism. Itshould be possible, he decided, to jamthe thing well enough to keep Rom from

sneaking in in the middle of the night."I'm going to need some wire and a flatchunk of metal the size of a—"

"First Lyell gets killed, and now Romgoes totally rock-happy," Adler went onas if Mitch hadn't spoken, "and all on asupposedly safe world. How are wegoing to look to the rest of the scientificcommunity?"

"We're going to look dead if we don'tget this door sealed," Mitch snapped."Now go get me—"

"Better dead than having to livethrough the end of a career," Adlermurmured. Mitch opened his mouth, butbefore he could speak Adler's eyesseemed to refocus on him. "What did yousay you wanted?"

"Some strong wire and a chunk ofmetal the size of a microscope slide,"Mitch repeated. "Try Rom's tool kit—and leave the laser here."

Adler nodded and headed off.Clutching the laser like a good-lucktalisman, Mitch waited tensely by thedoor, belatedly wishing he'd sent Katafor the equipment instead. But Adler wasback within five minutes with a doublehandful of wire, metal chips, and tools,and in ten minutes more the door was assecure as Mitch could make it. "At leasthe won't break in without making a lot ofnoise," he concluded, testing the latchone final time. "Come on—let's go findKata and Shannon and try to figure outwhat we're going to do."

"If you don't mind, I think I'll checkfirst to make sure Rom didn't unlatch oneof the windows for himself," Adler said,that distant look drifting onto his faceagain. "I'm . . . not likely to be much helpjust now."

With an effort Mitch controlled histongue. "All right. But don't take toolong. We're going to need your help."

A bitter smile tugged briefly atAdler's lips. "Sure. I'll do what I can . . .whatever little that is." Hiding hisgrimace, Mitch nodded and left. Hecould vaguely understand the demonsAdler was wrestling with, but thegeologist would just have to handle thebattle by himself. Kata was alone in thebio lab when Mitch arrived, staring

grimly at her computer display."Shannon?" he asked, pulling a chair

up beside her."I gave her a strong sedative and put

her to bed. What's the situation outthere?"

"Not good," Mitch admitted, eyeingthe screen. "We've got the door sealedagainst casual entry; but with Rom in aposition to keep us away from oursupplies, locking him out seems sort offutile. I've been trying to figure out away to sneak out in the dead of night tocollect some food, but if Romanticipates us properly whoever goesout there won't have a chance."

"Well . . . we've got a few days' worthof food already inside—more, if we

ration it. Rom's got to sleep some time.""Does he? We don't have any idea yet

what's happened to him. If he could beturned into a homicidal maniac, why notinto a sleepwalker with the samequalities, too?" Mitch nodded at thescreen.

"Rom's psych profile?""Yes," Kata nodded. "I was hoping to

find some basis for his actions—somelatent paranoia that had cancered out ofcontrol, maybe. But aside from his well-known loner tendencies nothing seemsparticularly abnormal."

"I doubt if Lyell would have broughthim along if there'd been anythingobvious." He hesitated.

"Stop me if this sounds weird . . . but

we know those guns were made by somealien race, and I told you Rom thought hewas hearing ghosts. Could . . . well,something have entered him and takencontrol?" Kata shook her head. "I don'tbelieve in ghosts, alien or otherwise."

"Maybe they weren't a corporeal raceto begin with," he suggested, a bitwarmly. It wasn't that ridiculous anidea. "It's possible they were pure spiritor pure energy or—"

"They fought with needle guns.""Oh. Right."Reaching forward, Kata blanked

Rom's medical record from the screenand typed up a new file.

"That gun's the key, Mitch—it's got tobe the gun." On cue, an x-ray view of the

pistol appeared on the screen. "He's theonly one who ever touched it, and allthis started at the same time." Abruptly,she called up a file index and leanedforward to study it. "On a hunch . . . Rommust have taken some ultra-high-resolution pictures. Let's see . . . ." Anew picture appeared and she centeredthe screen on one edge of the grip. "Let'stry about a thousand magnification . . . ."She pressed some keys, the picturechanged—and Mitch inhaled sharply.

The smooth edge had become a gentlycurving hill forested with squat butexquisitely sharp needles. A glance atthe scale confirmed his first guess: Romwould probably never have felt thempoking into his skin. "I think," he said,

"we've found the delivery system forthose nucleic acids in Rom's blood."

"I think you're right," Kata agreed."That angle must mean we're focused onone of the indented finger grips. Let'sjust confirm . . . ." She tapped controlsand the image rotated a few degrees."Yeah, the needles are hollow, all right.Probably take from that reservoir aroundthe magazine. Damn! Well, I guess thatanswers the how. All we need now arethe what and why." She drummed herfingers against the table. "And for atleast the what we're going to have tofigure out what that reservoir contains. Idon't suppose you have any idea of howto write an interior-analysis program forx-ray diffraction data?" Mitch snorted.

"Not hardly. But maybe we can get asample directly."

"From where?""From the gun's previous owner."

Mitch waved back toward the lab'srefrigerator.

"The tarsapien! Of course—I'dforgotten all about him. As a matter offact . . . ." She busied herself with thekeyboard again. Mitch, too, hadn'tthought about tarsapiens lately, but nowhe looked over at the corner whereSwizzle was squatting in a precarious-looking position on top of his junglegym. "Swizzle seems to have loosenedup from a couple of nights ago," hecommented.

"Yes," Kata agreed. "Whatever was in

that danger call he reacted to, he'sapparently decided since then that we'reokay." Her fingers paused, and Mitchlooked back in time to see her blinksomething from her eyes. "Moreevidence of intelligent modification ofinstinctual patterns . . . but I'll never getthe chance to convince Lyell now. Nevermind. Here's the biochemicalcomparison of the dead tarsapien withSwizzle . . . yes! Look—nucleic aciddifferences. Now, if only the moleculesdidn't degrade too much before the datawas taken . . . ."

In that, though, they were only halflucky. The odd nucleic acids had indeedbegun to unravel, and theirconcentrations were far too low for a

composite/extrapolation to be made."Well?" Mitch asked as a diagram of anincomplete molecule slowly rotated onthe screen. "Can you make any guessesas to what it's supposed to do?"

"I think so," she said slowly. "Thattail looks like a tag to get the moleculethrough the tarsapien brain-bloodbarrier, which implies we're on the righttrack. I've got a reasonable data base ontheir brain chemistry; and if worst comesto worst I suppose we could try andsynthesize some and give it to Swizzle."

"And then we come up with a way toblock whatever it does?"

"Starnation." Kata shook her head. "Ican't even think that far ahead right now.Let me do what I can with this and we'll

go on from there." Abruptly, she lookedaround. "Where's Adler?" Mitchfrowned, glancing back at the door. "Itold him to join us here. He's probablystill wandering around pretending he'son guard while he tries to figure out howhe's going to explain all of this to hiscolleagues."

"What's to explain? None of this is hisfault."

" I know that. But you try telling himhis life is more important than hisreputation." Kata said a word Mitch hadnever heard her use before. "Great. Justgreat. Between him and Shannon we'rereally rising to the challenge. Well,Mitch, until the rest of our team get theirbrains back on-line I guess it's up to us."

"Looks that way," he agreed. So herewe are, he thought, thrown together inbattle against something that'llprobably kill us if we cant figure it outdamn fast. How the hell do fictionwriters make this sort of thing sound soromantic?

But he had too many serious questionson his mind to bother with trivial ones aswell. "Okay," he sighed. "What can I doto help?"

Kata had known on an intellectuallevel since her senior year at college—and on a far more personal level sinceher first grueling year of grad school—that even the safest of sleep-substitutedrugs extracted their price in both subtleand not-so-subtle ways. Once she'd

finally accepted this truth she had madeit part of her personal rule book to avoidsuch drugs like Sirian leopard snakes.But rules were servants, not master, andit was almost without notice—let alonequalm—that she spent the next day and ahalf drugged to the eyeballs as sheworked to reconstruct and understand theenigmatic molecule that seemed to be atthe bottom of Rom's psychotic behavior.On one level, the results were worth theprice, as her studies began to bear fruit .. . but on another, it meant that whenAdler's fuse ran down that afternoon shewas in the worst possible shape tohandle it.

The explosion occurred an hour afterlunch—a meal which Kata had taken

care not to dawdle over. Adler'sgrowing touchiness and barelycontrolled nervous energy were hardenough to take by themselves, but whencontrasted against Shannon's almostghostly quietude the effect was to leaveKata feeling positively twitchy. Mitch,who usually managed to be an island ofrelative stability at such gatherings, wasback in his room catching a couple ofhours' sleep, and Kata had thereforestayed in the common room only as longas basic civility and hunger requiredbefore escaping back to the lab. She wasat her table, sweating over a particularlytricky simulation, when Adler stalked in."I need some ten percent hydrochloricacid," he growled, walking over to the

chemical cabinet. "Where do you keepit?"

"Number six locker; out the door andturn left," she replied without lookingup. "Help yourself." A second later sheliterally jumped out of her chair as thecrash of the cabinet door against thewall echoed through the room. "Adler!"she yelped.

He was fumbling with the back row ofbottles, his hand trembling. "Thehydrochloric, damn it!" he demanded.

"I told you I don't have any," shesnapped, dimly aware that she waslosing her temper but not really caring."What are you trying to do, earn yourselfa vacation in a psycho-ward snuggy?"His face darkened. "You'd like that,

wouldn't you? You'd like to be able tospread the blame around to the rest of us.You imply in your report that I wentrock-happy and maybe they won't noticehow badly you botched things."

" I botched things? What are youtalking about?"

"Not so eager to be in charge now,um? Now that Lyell's dead and Rommight as well be and you've got uscooped up in here like your pet tarsapwhile the whole project turns to organicfertilizer?"

"I am trying," she said icily, "to keepall of us alive. If this double-damnedproject and your triple-damnedreputation are that important to you, thenwhy don't you go out there and bring

Rom back in?"I might just do that," he snarled.

"You'd at least have to list me as a heroif I did." Turning, he stomped back out.

Slowly, the blind fury died withinKata, and as it did so she started toshake with reaction and guilt. Someterrific leader I am, she berated herself.Lyell wouldn't have blown up like that—he'd have let Adler drain off some ofhis tension and that would have beenthe end of it. Obvious thing to do. Butinstead she'd fought back, and in theprocess simply added to both parties'resentment. I can't believe I didsomething that stupid. Stupid and—

Did I really suggest he go out afterRom? Oh, my God—

She didn't even stop to put her half-finished program on standby as she tookoff toward the exit as fast as the curvingcorridor permitted. If Adler was feelingas irrational as he'd sounded . . . . Butthe exit door was still sealed when shearrived. For a moment she leanedagainst it, catching her breath and feelinga little silly. Of course Adler wasn'tcrazy enough to—

"Out of my way, Kata," a voicebehind her growled, spinning her aroundand kicking her heart back into high gear.

Adler had put on gloves, hat, and theheaviest coat he had, and had a hip packbelted to his left side. With the laserriding his other hip he looked like achild's version of a Starlane Patroller,

and under other conditions the effectmight have been laughable.

But there wasn't anything amusingabout the expression on his face.

"Adler, this isn't going to do anygood," Kata said carefully, stayingwhere she was. "You don't knowanything about hunting animals, let alonepeople; and even if you did Rom's got aflashless weapon and his pick of placesto ambush you from. All you canpossibly do is get yourself shot."

"You agreed yourself that whathappened to Lyell was an unlikelyaccident," Adler pointed out. There wasa deadly calm to his voice that suggestedreasoning with him was a waste of time."A few needles, if he gets that lucky,

won't slow me down much—and myweapon is ultimately superior to his."

"Lyell's death was an accidentbecause tarsapiens don't have the eye-hand coordination to be marksmen,"Kata retorted. "Rom does. Furthermore,he also knows where the vital organsare, and he's had plenty of time topractice his shooting. Chances are goodhe'll kill you before you even get a shotoff."

Adler's lip twitched. "And if he does?My career will never have time torecover from this trip, Kata. I might aswell die here as live out my last fewyears in some tenured dead-end positionsomewhere."

"Adler, that's—" She broke off before

the work crazy could slip out and triedagain. "Look, this isn't going to be nearlythe drag on your reputation that you seemto think. The alien gun actually qualifiesas pretty exciting stuff—"

"For you, Mitch, and Shanon,perhaps," Adler interrupted her. "But forme? No. I'll just suffer under thesensationalistic hammer without so muchas a new geological formation tobalance it with." Again, his lip twitchedin an almost-smile. "I've seen it happenbefore; been the target of it, in fact, morethan once. Colleagues—people youthought were your friends—concentrating on everything but the paperyou're presenting or the results you'rereporting on. 'But what really happened

on Draconis Minor, Dr. Zimmerman?''Do these two really fight as much inprivate as they do in the journals?' "'How were you involved in that incidentwith the site break-in?' I can alreadyhear what they'll ask me about Pallas:

'So things were falling apart, eh?What did you do to help out? Oh, youstayed in your room and sorted rocks?How help ful of you.' "

"Adler—""No, Kata. When they ask those

questions I intend to have answers forthem." Carefully, he drew his laser andsettled it firmly into his gloved fist."Please; just go away. I really don't wantto have to hurt you."

Wordlessly, Kata moved aside. Adler

knelt by the door and within half aminute had undone the makeshift lock."Seal it up behind me," he instructed her,getting back to his feet. "If I get Rom I'llcall you." Taking a deep breath, heabruptly swung open the door andslipped outside. Only then did Kata'sdrug-fogged mind think to call for help.

Mitch was obviously still half asleepwhen he answered her call; but he wasn'tthat way for long.

"Stay there," he told her when she'dgiven him a two-sentence summary ofthe situation. "If anyone heads for thedoor, holler. I'll get the other laser andmeet you there in a couple of minutes."He was there in less time than that, theweapon in his hand forming an odd

contrast to his robe and disheveledappearance. "I've got Shannon warmingup the Lostproof monitor," he said,glancing out the window. "Did he get tothe trees?"

"I don't know—he broke to the leftjust past the sheds. Mitch, I'm sorry—"

"Never mind the brow-beating," hecut her off. "Get back there and helpShannon. And leave your comm open."

It was a slow and painful wait.Despite his apparent recklessness Adlerwasn't simply beating the bushes andwaiting for Rom to attack. His blip onthe Lostproof screen showed he was infact making his way slowly and—presumably—quietly through the forest,halting occasionally in the shadow of a

tree before continuing his rough spiralaround the clearing. Each time hestopped Kata's stomach tightened,relaxing again only when he startedmoving again.

He was almost halfway around whenhis blip abruptly threw itself sideways."Mitch!" Kata barked.

"I think he's been hit.""Where?" her communicator snapped."Thirty-five meters by forty-two

degrees," she read off the coordinates."Okay. Come here and take the laser

—I'm going to take the Sunray up.""But Rom—""If he's with Adler I've got a clear

path," Mitch cut in impatiently. "Hurryup; I don't want to just leave the laser

here on the floor."She hurried, and two minutes later the

Sunray hummed its way overhead in thedirection of Adler's motionlessLostproof blip. A minute after that Mitchcalled in the bad news.

"There's just no way at all for me toget in on top of him," he reportedtensely. "I'm going to have to put downand go out to get him."

"No," Kata snapped, the pain of thedecision twisting like a knife in her gut."It's too risky—you'd be a walking targetout there."

"Kata, I can't just leave him—""You have to. Maybe Adler's not

dead; if so, you may have distractedRom's attention enough to let him

escape. But if you wait too long Rom'llhave time to get back before you—andhe'll then be in perfect position to shootyou when you try to come back inside."

For a second she thought he was goingto refuse . . . and that she would beforced to add another death to herconscience. "All right," he sighed. "I'mcoming in." She sat in the common roomfor a long time after Mitch made it in,staring into a cup of coffee and tryinghard not to break down into borderline-hysterical sobbing. Those damn drugs,she told herself over and over; but sheand the others knew better than that. Katasimply didn't have what it took to playchess with people's lives.

Oh, Lyell—why did you have to will

this burden to me?"That coffee's going to curdle if you

don't drink it," Shannon murmured fromacross the table. The attempted humordeserved an attempted smile, which wasabout all Kata could manage. At leastI've got Shannon acting human again,she thought, sipping her cooling drink.Maybe if I'd fallen apart sooner noneof this would have happened. Is that anirrational thought?

"Nothing seems to be moving outthere," Mitch said as he came into theroom and sat down next to Kata. He'ddressed and run a comb through his hair,but such trappings of normalcy merelyemphasized the tension lines about hiseyes. "I can't tell for sure, but it looks

like Adler's Lostproof blip may havemoved slightly. That could mean he'sstill alive and conscious."

"You can't go out after him," Kata saiddully.

"I wasn't going to ask." He paused,and she could feel his eyes on her. "Youmade the right decision, you know. Makethat decisions, plural. There wasn't athing in the world you could have donefor Rom, Adler was stir-crazy beyondrational argument, and I probably wouldhave gotten myself perforated if I'd triedto get him into the Sunray."

"You pointed out to me two days agothat we'd have trouble if I kept everyoneindoors," Kata said, perversely refusingto be comforted. "I should have listened,

tried to do something about it.""There wasn't anything you could have

done," Shannon put in quietly. "In fact, Irather think driving us stir-crazy was thebasic idea behind all this."

"All what?" Mitch frowned. "Youthink someone's out there trying to driveus off Pallas?" Shannon shook her head."Not us personally; and I don't thinkanyone's actually watching us. What Imeant was that whoever left the gunshere did so specifically to keep peoplelike us off the planet." Kata's firstreaction was incredulity . . . but even asshe opened her mouth to voice herdoubts the pieces started clicking intoplace. Multiple-shot, maintenance-freeweapons in the hands of native animals;

combined with the lab results of the pastfew hours—

Mitch might have read her mind."Kata, have you got anything on that oddnucleic acid yet?"

"Yes." She took a deep breath. "Theresults aren't complete by any means, butit appears the drug is designed to teachany tarsapien who finds the gun how touse it. And, if Shannon's right, exactlywho to shoot it at."

" I t what?" Shannon whispered."How? I mean, memory alterationmethods are supposed to require hugetemporal-lobe induction machines."

"Ours do," Kata acknowledged. "The—what do I call them? How about the'Gunners'? The Gunners seem to have

come up with a method using nothing buta sequence of enzymes to stimulate andguide the false memory development.How they provide the motivation I don'tyet know, but it would have to couple arecognition pattern with either aglandular or mental fear reaction andthen induce the proper physical motions.Probably need a reinforcementmechanism, as well—" She cut offabruptly.

"Sounds awfully dicey," Mitch shookhis head. "To coordinate that manydifferent activities within such a shorttime of each other?"

Kata shrugged. "I argue from theresults that they managed it."

"Even worse, how could they

possibly set up a recognition pattern thatway? You'd need sensory input of somekind—" He paused. "Oh. Sure. All ofthat winds up as chemical signalsanyway. Why not just skip themiddleman?"

"That seems to be the case," Katanodded. "Part of the molecule appearsdesigned to break away along with oneof the several tags. The tags on mysample have degraded pretty far, but theone that's most intact looks suspiciouslylike it should attach itself to a group ofreceptor sites found mainly in the brain'svisual cortex."

"Human or tarsap?" Shannon asked."Either, as it turns out." Kata

hesitated, then continued. "I'm afraid

that's what's happened to Rom. We mustlook enough like the Gunners' enemies tohave triggered the chemical sequence."Mitch bit at his lip. "If that's true, though,why'd they wait six months before theystarted shooting?"

"Probably took that long for the oneswith the guns to get here once theylearned about us," Kata shrugged."Remember Swizzle's morning newsservice? I guess the tarsapieninformation network is even moreefficient than I thought."

"Um. That would explain why Romand Shannon didn't get shot at out at thevarious ruins, too, wouldn't it? Theydidn't spend enough time anywhere forthe gun carriers to catch up with them."

Shannon's eyes held a faraway look."That morning—the last one he was here—Rom looked like he hadn't slept allnight, and I suggested a shower andshave might make him feel better. Hetook a shower, but didn't comb his hairand absolutely refused to shave. Ithought he was just being grouchy . . . butnow it makes sense. He didn't want tolook in a mirror."

"Because he knew he'd see an enemy."Mitch looked at Kata. "So you're sayingwhat we had here was a sort of wind-upproxy war. The Gunners didn't want torisk their own lives pushing theirenemies off Pallas, so they armed thelocal animals and turned them loose todo it." He shivered visibly. "What a

cold-blooded scheme.""It gets worse," Kata sighed.

"Remember Rom's report?—the gunsarrived here long before the settlementswere put up. The Gunners weren'tthrowing anyone off; they were makingsure no one showed up in the firstplace."

"Disputed planet? But then why didn'tthe Gunners move in to colonize?"

"Maybe they lost the war. Or maybethey never wanted Pallas in the firstplace."

"Meaning?""Well, one of the first things we did

here was make sure the forest didn't gettoo close to our buildings," Kata said,waving out the window at the herbicide

ring. "Maybe we're sitting on part of theGunners' own cordon sanitaire."

There was a long silence."Incredible," Mitch said at last, shakinghis head. "Seal off a whole planet—maybe a whole group of planets—tokeep your opponents off your doorstep.You know, I never thought about itbefore . . . but have you noticed that thegun's finger notches angle upwards, andthat the angle is steeper for the lowernotches? Means a creature with a smallhand and thin fingers will get about ascomfortable a grip as one with largehands and thicker fingers."

"Which implies they can parachute thethings wholesale onto practically anyworld with DNA-based life and some

species there will likely be able to usethem," Kata said. "In fact, I'd bet even atentacle or prehensile tail could get anadequate grip. Add an attractive scent orcoloring to the guns to get the wholething started, and the system probablyperpetuates itself—you can just go awayand forget it. Makes sense. Makes a lotof sense."

"So what are we going to do aboutRom?" Shannon asked.

The grand vision of interstellarrivalry collapsed like a popped balloonback into the life-and-death problem athand. "I don't know yet," Kata admitted."Bear in mind that we're not reallyfighting Rom, or even the tarsapiens—we're fighting the damn aliens who built

these guns in the first place.""But it's Rom who's actually shooting

at us," Shannon sighed, adding the partKata had intended to leave unsaid. "Iunderstand. What can I do?"

Back to being in charge, Katathought, the reminder an almost tangibleconstriction around her chest. "Stay bythe Lostproof and watch both Adler andthe transponder in his laser; holler ifeither of them moves. Mitch and I'll getback to work, see what we can come upwith." Mitch was silent all the way backto the lab, but once inside he let out ahissing breath. "The laser," he muttered."Somehow, I never even thought of that.What are we going to do if Rom startsshooting at us with that?"

"I don't think he will," Kata sighed,slumping into her chair. The drug-enhanced depression was fading, to bereplaced by fatigue. "Aside from the factthat carrying it lets us trace him . . . well,I didn't want to mention this in front ofShannon, but the Gunners did indeed adda cute reinforcement kicker to theirtraining method. I've located a set oflow-power electrodes on the grip andfiring button that seem to send signalsalong the sensory nerves to the brain,where they induce their versatile littlemolecule to briefly jump enkephalinproduction."

"Like a poke in the pleasure center,"Mitch grimaced. "No wonder hewouldn't let anyone take it away from

him. That sort of stimulation is supposedto be pretty addictive, too, isn't it?"

"It sure is." Kata shook her head."Mitch, we're in way over our headshere. How can we possibly fight alienswho we've never even met? We don'thave anything but the vaguest idea whatthey were trying to accomplish with theirguns."

"Well . . . ." Mitch bit at his lip as hegazed out the window. "It's pretty clearthat, whatever the details, the schemedid work—remember Shannon telling usthe ruins were abruptly abandoned?Now, similar biochemistry or not, Irefuse to believe we fit the target profileexactly. If we can reproduce theGunners' thinking well enough, we may

be able to find a loophole somewhere."Kata snorted. "May I repeat, we don'teven know what they looked—"

"For instance," Mitch overrode her,"they weren't trying to prevent militarybases from being built here. Soldierswith body armor wouldn't be botheredby the needles. Underground or fullyenclosed bases could've been built, too,but they weren't. So question: why didthe—let's call them the Rivals

—why did the Rivals need to wanderaround outside without armor?" Katafrowned thoughtfully, impressed in spiteof herself. In a handful of sentencesMitch had converted a seemingly infiniteproblem to one with almost manageabledimensions. I should have been able to

come up with that, she groused toherself. Come on, brain: back to work."Maybe it wasn't the Rivals themselvesthat were the target," she suggested."Maybe their food supply included agrazing animal that had to be keptoutdoors."

Mitch nodded slowly. "Or else thetargets were unarmored civilians. Eitherway, we're talking about a permanentcolony rather than a military base."

"So point one: the scheme wasdirected against permanent settlements."Kata yawned widely enough to make herjaw hurt. "Pretty odd cordon sanitairethat doesn't care if the enemy bringstroops through, though. Or am I just tootired to think straight?"

" I t does seem odd; but you verydefinitely are too tired for a think-tanksession," Mitch told her.

"Let's postpone this until you've hadsome sleep."

"You sound just like Lyell," shesighed. "His Standing Order Number Sixwas always 'go take a nap.' "

A shadow seemed to pass overMitch's face. "I'm sorry; I didn't mean to—well, remind you of—whathappened."

"It's likely to be hard to forget for awhile," she replied dryly.

"Yeah." He hesitated. "You cared alot for him, didn't you?"

"Lyell? Of course. We worked forseven years and three planets together."

"I meant—never mind."It was just one more indication of her

fatigue that it took several seconds topick up on what he was trying not to say."If you meant on a more personal level,the answer is no," she said. "Lyelloffered the best opportunities to dobiology— real biology, not the robot-line busywork multiversity expeditionsparcel out. He was a good boss andcolleague, but I wouldn't have evenconsidered any other kind of relationshipwith him."

That seemed to surprise him. "Whynot?"

"Oh, come on Mitch—you saw howShannon reacted when Rom first ran outon us. She was all set to go out and get

herself killed. Even now she's not allthat functional. That's what deeprelationships do to you—foul up yourmind as well as your glands."

"Well, at least she's worried aboutsomeone besides herself," he repliedwith unexpected heat.

"What about Adler, who couldn't thinkof anything except his preciousreputation? Is that more rationalthinking?"

"No, but who said I had to be likeeither one? Anyway, don't we havebetter things to worry about right now?"

"You're right." Mitch rubbed at hiseyes. "Sorry. Look, why don't you tellme what I should do here and then go getsome sleep. The chance that Rom's

getting addicted gives us a tighterdeadline than we used to have."

"Right." Now what, she wondered,was that all about? But she was too tiredto puzzle over Mitch's reaction. It wasprobably just the tension, anyway.

Mitch got the machine going on thesimulation Kata had requested, and thensat back and glowered at the flickeringindicator lights. So much for riding intothe sunset with her after all this wasover, he thought, embarrassmentflooding his face with warmth. To havemissed that badly on such an assumption

. . . and the truth, naturally, left him injust as hopeless a position as before.Kata cherishing Lyell or his memorywas bad enough; but if she hadn't fallen

for him, then Mitch was completely outof the running. I wonder if she noticedhow close I came to making ablithering idiot of myself? Maybe Romwas right—maybe I ought to trade inthe rest of my teen-age romanticism forsome healthy cynicism. It wasn't anespecially original idea; he made similarresolution every time one of his castlesin the sky fell on top of him. Though if ittook Rom ten years of marriage to getthat way—

His communicator beeped, cuttingthrough the flood of self-reproach. Kata?he wondered, rather hoping it wasn't."Yes—?"

"Mitch, Adler's blip is beginning tomove," Shannon's voice cut him off. The

conversation with Kata was abruptlyforgotten. "Which way?" he snapped.

"Parallel to the herbicide ring—theLostproof shows a shallow furrow rightthere. And his laser's moving with him."

Adler trying to find cover? Or Romdragging the body out of the way? Theremight be a way to find out. "Keepwatching," he told her. "I'm going to thedoor to try and get Rom's attention."

"Be careful.""You bet."No one was visible through the exit

door window when he arrived, but henevertheless had his laser in hand as heunsealed the door and eased it open."Rom?" he called tentatively. "Rom, Iwant to parley." He held his breath, eyes

and attention focused toward the placewhere Adler's blip was moving.

"We've got nothing to talk about,"Rom's voice wafted in from the forest.From the forest—but nearly forty-fivedegrees around the circle from where itshould have been. Mitch let his breathout, feeling better than he had in hours.Score one for our side—Adler's stillalive. Now, what do I say to Rom?"We're willing to leave here, Rom," heimprovised, hoping their guess about theGunners' intentions was at least close."Would you give us safe-conduct to theSunray?"

"So you can either hunt me down orjust set up somewhere else? Forget it."Mitch grimaced; but unfortunately it

made sense. Whatever the Gunners'actual goal, they wouldn't have botheredprogramming the details into theirpawns. "We don't want to hunt you down—we want to help you," he called. "Thegun you've got is giving you a false set ofmemories and motivations, making youthink we're your enemies. But we're not—"

"You think I don't know who myenemies are?" Rom cut in harshly.

"Rom, listen to me! The enemies theghosts are telling you about?—they leftPallas hundreds of years ago. They'regone; all of them—the abandoned ruins,remember? What you're trying to do ishammer us into the mold the ghosts aregiving you. But we don't fit; try and see

that. We aren't the ones you need to beafraid of—"

"No! You're just trying to confuseme!"

"Rom—"Mitch dropped back, losing both his

sentence and train of thought as a needlericocheted off the door jamb andwhistled past his ear. Slamming thedoor, he hurriedly sealed it and returnedto the common room.

Shannon looked ten years younger. "Italked to Adler," she announced beforeMitch could speak.

"He heard you and Rom shouting anddecided to risk calling me."

"And?""He's very weak and tired, but said

he'll be okay for a while unless he getsshot again. He thinks it was a tarsap thatgot him, not Rom, and he only took fouror five needles before it ran away."Mitch nodded; Rom would certainlyhave known enough to stay and finish thejob. Using herbivorous animals to fightfor you does have some disadvantages,he reminded himself. "Any of theneedles hit vital organs?"

"He didn't think so, but he twisted hisankle when he fell, which is why he can'tget back." She hesitated. "He also saidRom almost found him when you buzzedthe area in the Sunray, but that he leftwhen you did."

Mitch felt his stomach tighten. So notonly had his quixotic rescue mission

failed, it had nearly gotten Adler killedin the bargain. I'd better quit trying tobe a hero before I lose every friend I'vegot, he thought bitterly. "Four or fiveneedles, you said?"

"Yes. I told him he'd be able tosurvive that much of the drug." Her eyeswere very steady on him.

"Was I telling the truth?""I hope so." Though on my record to

date . . . . "Did you hear any of my talkwith Rom?" She shook her head.

"I tried to get him to see that themotivations the Gunners' drug is givinghim don't make sense. But he wouldn'tlisten."

Shannon was silent a long moment. "Iknow next to nothing about

biochemistry," she said at last,"but I wonder if it's possible you and

Kata are overcomplicating things withthis recognition pattern to fear reactionto specified physical response sequence.It seems to me that, since most animalsalready have their own inborn enemy-recognition apparatus, the Gunners couldsave one or more steps by linking themost obvious physical characteristic oftheir enemies directly into this existingpattern. That also solves the timingproblem, because the memory matrix forshooting the gun can be learnedessentially independently and storedaway until needed."

Mitch frowned. "An interesting idea. Idon't know how the chemistry would

work out, but it sure sounds simpler thanKata's description. Though it seems tome Rom would need more than hisnormal dislike of us to explain thedrugs's effect on him. He'd almost haveto see us as enemies, wouldn't he?"Shannon sighed. "Mitch, Rom sees theentire human race as his enemies. Not inthe way you think," she added as his faceapparently mirrored his reaction. "He'snot paranoid in the sense that he thinkspeople are deliberately out to get him.It's more like he's a kitten stuck in aroom with a hundred clumsy elephants.He's convinced that, whether we mean itor not, we're all likely to end up hurtinghim."

"That seems a pretty extreme

reaction," Mitch frowned. "Sure, we allbump egos occasionally—" his lastexchange with Kata rose up to mock him— "but that's no reason to bury yourselfin—well—"

"In archeological digs on desertedplanets ?" Shannon's smile was brief andpainful. "Not for us, no. But Rom'salways been hypersensitive to peeropinion and he takes such ego bumpsvery hard. The roots of this go back toearly childhood, to times and places hewon't even talk much about with me."

"Um. And that hardhead image heprojects—the defense of a strongoffense?"

"Yes. Actually, he was a lot worsewhen I first married him. He's relaxed

quite a bit lately, with more habit thanreal intent behind his cynicism. I'm . . .worried about what this is going to do tohi m." Not to mention to us, Mitchthought, but kept that depressingreminder to himself. "I'll discuss thiswith Kata when she wakes up, but I don'tknow offhand how it'll help. At themoment we're sort of trying a differenttack." He started to get up, abruptly satdown again. "Frensky moss—what am Iusing for brains? Listen—you're theresident expert on reconstructing humanand alien cultures out of minusculepieces, right? Let me tell you what we'retrying."

Quickly, he sketched out the logic heand Kata had tried to apply to the

Gunner-Rival conflict and thedeductions it had led them to. Shannonlistened, gazing off into space, and whenhe'd finished she nodded. "It makessense," she told him. "We found one ruinwith an expanding series of outer walls,useless for serious defense but perfectlyadequate for stopping those needles.Either your civilian courtyard or grazingarea models would fit with that."

"But I keep hitting the question of whythey didn't simply wear body armoroutside; they or their animals. After all,people in cold climates regularly bundletheir children into snowsuits when theyleave the house. This wouldn't be all thatdifferent."

"Perhaps, but you're missing an

important psychological point.Colonizing a world— really colonizingit—is possible only when you can liveout under the open sky without anythingthat can be termed life-support gear. It'slike that for humans, it's like that forvirtually all the intelligent races we'vecome into contact with. You may have toimport your water or flood your cropswith compound nitrates, but if you canstand outside with the wind and sun inyour hair you can believe down deepthat the world is yours. If you can't—"She shrugged. "You wind up with a baseinstead of a colony. Luna was the firstexample; there've been dozens sincethen."

Mitch digested that. "So you're saying

that, for some reason, the Rivalswouldn't settle for bases. Why not?"

"I don't know, and we may never findout. Perhaps they were too sociallyoriented to exist in small groups;alternatively, perhaps one gender or theother couldn't or wouldn't adapt tostaying indoors all the time. It certainlylooks like they tried to hold out; theywere clearly here for years beforegiving up. There's also the possibilitythat the Gunners had more powerfulweapons that they had qualms aboutusing against civilians. In that case, theRivals would know that setting up apurely military base on Pallas would bea waste of time." She thought for amoment. "Is there anything you could get

on the Rival biochemistry if you assumethe needle drug was more lethal to themthan it was to us?"

"Mm. I don't know how we'd getanything conclusive from it. There mustbe hundreds of ways the drug could kill,depending on what specific part of thesystem it attacks. Kata might be able tonarrow it down some, but I'm not surehow it would help us in any case. Wealready know what it does to us, afterall, and that's the really critical thing atthe moment."

"True," Shannon murmured. "I wasjust looking at the puzzle pieces wehave, trying to see what we can do withthem. Are you assuming the Gunnersnever intended to colonize Pallas

themselves?""Or else that the Rivals somehow

prevented them from doing so. Is itimportant?"

"Well . . . when an army mines asection of land, they usually leavethemselves the option of locating andclearing those mines away at some futuredate—"

"We've already shown our sensorsaren't good enough to find the guns."

"—or of deactivating them."Mitch opened his mouth, closed it

again. "Deactivating. Now that's aninteresting thought. Any ideas how youmight do that?"

"It can't be an easy method to stumbleacross," Shannon said, gazing into space

again. "Ideally, it should be somethingthe Rivals couldn't do even if they knewroughly how."

"A coded radio signal, perhaps?Something involving the power pack orsequencing in the magnetic rings?"

"Or maybe something involving thatsensor Rom mentioned—the one in themuzzle of the gun."

"Point it at a Gunner and it shutsdown?" Mitch suggested, feeling acautious excitement growing within him.If they could figure out the mechanismand trip it themselves . . . . "No, thatwould be too easy. A cardboard cutout,or a Rival in a Gunner costume—" Hestood up. "Let's go back to the bio lab.Some more data should be ready on the

instinct-drug molecule by now, and wecan see what Rom found out about thatmuzzle sensor. Give me a hand with theLostproof gear; we'll take it with us."They spent the rest of the afternoon goingover the gun analysis with a fine mesh,but the results were disappointing. Themuzzle sensor itself showed insufficientdetail on any of the x-ray photos for themto get more than the vaguest idea of whatit actually did. There was an opticalcomponent to it, certainly; but there wasalso a magnetic detector coil andsomething else that Mitch couldn't evenhazard a guess about. The connectionsbetween all of it and the rest of the gunwere equally cryptic, and they spent afrustrating half-hour tracing one optical

fiber on the high-resolution x-rays onlyto have it disappear into anotherenigmatic component.

And as the initial excitement fadedinto the disappointments and blindalleys, Shannon seemed to withdraw intoherself, offering comments less and lessfrequently until she merely sat in herchair and watched Mitch work. By thetime Kata reemerged from her room thearcheologist had drifted even fartherfrom both the lab table and theinvestigation and was standing by thewindow gazing outside. Kata's owninitial enthusiasm slipped somewhat asMitch described the lack of progress, butit was clear she intended to be asoutwardly optimistic as possible.

"I think you've hit the nail dead-center, Shannon," she nodded. "Youreally wouldn't want to scatter suchlong-lived weapons indiscriminatelyaround and not be able to either locateor shut them down. Why don't we startwith that sensor again; maybe I'll seesomething you overlooked."

"Maybe." Shannon took a deep breathand turned to face them, and with ashock Mitch saw that the laser he'd lefton the table beside the Lostproofmonitor was now dangling loosely fromher hand.

"But you'd better work fast . . .because in one hour I'm going to trybringing Rom in." She's finally snapped,was Mitch's first frantic thought; and

what the hell do we do now? his second.Beside him Kata straightened up and hewaited tensely for her reaction. But itwas far milder than he'd feared. "Bereasonable, Shannon," she said calmly."Rom will shoot you on sight; you knowthat."

"Maybe not." Shannon's voice wasalso calm, but with an undertone ofblack tension beneath it. How long sinceshe's had any sleep? Mitch wonderedabruptly. Just because she hadn't beenable to help with any of the work thepast couple of days didn't mean she'dbeen relaxing. In fact, her forcedidleness might have made things evenharder for her. "If this whole enemy-recognition thing is right," she continued,

"then I'm the only one among us who hasany chance at all of getting to him. Theonly one who might register as a friendeven through the drug's influence."

"And what if you're wrong?" Katacountered. "You'll be throwing your lifeaway for nothing. At least give Mitchand me a few more days to follow thislead down." Shannon shook her head."We can't wait that long. Every minutewe spend here means more of that druggoing into Rom's blood and brain. At themoment he seems to be fighting it, atleast to the extent of being willing to talkto us. But that can't last—you know thatbetter than I. I've got to try this before heloses the battle completely . . . beforethe drug becomes a permanent part of

him." Mitch glanced up at Kata, saw herjaw tighten. So much for keeping thepossibility of addiction secret, hethought. "You're still risking your lifeunnecessarily," he put in.

"Am I? What about Adler?"Mitch's argument died in his throat.

"Yeah. Adler.""He's going to need medical attention

soon, not to mention food, if he's goingto survive," Shannon pointed outunnecessarily. "And the longer he's outthere the greater the chances that Rom oranother armed tarsap will come acrosshim."

"And what if a tarsapien comes acrossyou?" Kata asked.

"I'll just have to risk that, won't I?"

Shannon smiled, and Mitch saw that herlower lip was trembling.

"Please, Kata; I know you don'tunderstand why I have to do this, butyou're just making it harder for me to bebrave. Don't make me fight you andMitch—I can't handle that along with allthe rest of it." For a long moment the twowomen stared at each other across theroom . . . and finally Kata sighed. "I'llcompromise with you," she said. "Youoffered us an hour; but by then the sunwill be almost down and the forestalready getting dark. The last thing youwant is for Rom to mistake you for me inthe gloom. Give us until morning andwe'll let you try it, whether we've gotany results or not. Okay?" Shannon's lips

compressed into a thin line. "What aboutAdler?"

"My guess is that he can survive thenight if he makes it to sundown.Certainly it won't get too cold for him,and the tarsapiens will be quiescent untilalmost dawn, as well. If he was able tomove and talk soon after he was shot, Idon't think the needles he's carrying aregoing to kill him."

"But you don't know for sure."Kata shrugged. "It's at least as good an

assumption as the one you're going on."Shannon smiled briefly. "All right.Dawn tomorrow, then. Your word?"

"Yes." Kata extended her hand, palmup.

Stepping forward, Shannon laid the

laser across it. "I'm going to my room,"she said. "Let me know if there'sanything I can help with."

"Sure," Kata said softly. "We'll be upto see you out." Shannon nodded and leftthe lab. "You going to let her go?" Mitchasked Kata, not sure which answer hewanted to hear.

Kata sat down. "I promised her shecould," she sighed. "Besides, she's right.On all counts."

"Except maybe the point about herbeing off Rom's enemies list." Mitchhesitated. "When I was doing that lastmedcheck on Rom he said somethingabout Shannon being an enemy alongwith the rest of us. I think they must havehad a fight or something."

"Oh, terrific." Kata closed her eyesbriefly. "Well, that just makes it all themore crucial that we find a way to shutdown those guns." For a moment shegazed out the window, fingers tapping onthe lab table. "Along with all we don'tknow about the Gunners, we do knowthat they were whizzes with complexorganic chemistry—the instinct drugshows that. Maybe we should be lookingfor a chemical cutoff switch instead ofan electromagnetic one or whatever."

"You mean something you set off likea gas bomb upwind of the guns?" Mitchasked doubtfully.

"Sure. You've already admitted there'sa component of the muzzle sensor youdon't understand."

"Agreed; but we're back then to thequestion of why the Rivals wouldn't beable to do that themselves. Not tomention the mechanics of how a whiff ofgas would set up that kind of signal."

"Let's forget the mechanism for now."Kata pursed her lips. "Could they neverhave gotten ahold of a working model . .. ? No. Even if the Rivals could betrapped by the gun like Rom was, theysurely must have figured things outquickly enough to have safely studied atleast a couple of the weapons. And it'spractically guaranteed their equipmentwas more elaborate than ours—theywere a settlement, after all."

"So they must have figured outeverything about the guns," Mitch

concluded. "And they gave up and leftanyway. Not a good sign."

"Let's not give up ourselves just yet,"Kata said tartly. "What about multipledesigns? A hundred different varieties ofcutoff switches, say."

"Should've just taken them longer toclear the planet. Remember, they wantedPallas—they had settlements alreadybuilt—and they would hardly have quitwithout a fight."

"Which puts us right back at squareone," Kata murmured. ". . . Unless it wasa cutoff the Rivals couldn't use."

" 'Couldn't'?""Say the cutoff was a poison to them

—a heavy, viscous chemical that'll coatthe ground and foliage. That would've

eliminated the guns but left them just asbad off."

"Interesting idea," Mitch said slowly."Especially since what's poisonous tothem might not be so to us.Unfortunately, that also means we don'thave the foggiest idea what sort ofchemical to try." Kata sent him a tightsmile and scooted her chair up to thecomputer terminal. "Sure we do;because the Gunners almost certainlyloaded their needles with the nastieststuff they could think of." A moleculardiagram appeared on the display inresponse to Kata's commands, and for along moment she gazed at it. "I supposewe could try to synthesize some of thestuff and shoot it into the forest, but I

hate to do that without knowing exactlywhat it'll do. If we had better data on themuzzle sensor we could try a simulation.But barring that . . . wait a second."

Again her fingers skipped across thekeyboard. "This is a weird idea, butsince the actual mechanism is a completeunknown anyway, let's see what happenswhen the needle drug meets the instinctdrug . . . oh, my God."

"What?" Mitch snapped.Kata's face had turned an ashy white.

"Wait a minute—I want to try it againwith a larger target population."

The display images shifted twice."Well?" Mitch demanded.

Kata seemed to shrink in her seat."Catalytic reaction," she said with a

shiver. "You get anything upwards of adozen needle-drug molecules into thegrip resevoir and it'll break the entiremass of instinct drug into five separatetypes of cyanide . . . the whole thingunder pressure."

"Pressure? As in to drive it throughthe delivery system all the morequickly?" Mitch hazarded, a funnyfeeling in the pit of his stomach.

"Yeah. So if you're not a Rival, allyou need to do is spray the forest withRival-killer . . . and all the tarsapiensholding the guns fall over dead."

Mitch broke the silence that followed."Well. So much for that approach.Unless you think this is possibly just acoincidence?"

Kata shook her head. "The chemistry'sbeen too carefully set up to be anythingbut deliberate. This is the Gunners'cutoff switch, all right. And they've gotus as neatly stymied as they did theRivals." Unless and until, Mitch addedsilently, we decide Rom can't be saved.The whole idea made his stomach churn. . . but down deep he knew they mighteventually have to make such a decision."They must have been really great tohave on your side in a war," he growled.Kata reached over and blanked thescreen. "It shouldn't be all thatsurprising a revelation, actually—ifthey'd cared a tuft of Frensky moss aboutthe tarsapiens they wouldn't have turnedthem into cannon fodder like this in the

first place. What would they care if afew more got killed?" Another silencedescended on the lab, and Mitch foundhimself gazing out the window. Nowwhat?

he wondered bleakly. Our bestchance, and the Gunners have alreadyclosed the door on it. We can't letShannon go out there now—promisesor no. If Rom doesn't get her thetarsaps will, and there's not a thing—

The train of thought vanished, buriedabruptly beneath a realization that wasso obvious he was astonished it hadn'toccurred to him earlier. "Kata," he saidcarefully. "What's keeping Rom alive?"She turned puzzled eyes on him. "Youwant to specify?"

"He's been out there two days now,"Mitch said, "out with one or moretarsaps who—"

"Hell and breakfast," Kata breathed."You're right, Mitch. For some reasonthey aren't shooting at him."

"If we can figure out why—""Yeah, yeah," Kata shushed him. "Let

me think." She bit at her lip. "Shannonmust have been right— it's thetarsapiens' enemy-recognitionmechanism that's being used . . . and it'snot a visual one. Rom surely doesn'tlook any different; but with a new set ofenzymes in his system he must smelldifferent. Enough different, anyway—and that gives us our own defensiveapproach." Mitch looked over at

Swizzle in his cage, for the first timereally seeing the huge nostrils. "We mustbe right on the edge of the Rivals' scentpattern for that small a change to protecthim, though," he pointed out. "Theproblem will be to make sure we don'tuse a perfume that pushes us the wrongdirection."

"Oh, we can do better than that," Katasmiled—her first real smile, Mitchthought, since this whole thing hadstarted. "We know at least one otherodor the tarsapiens don't shoot at— andhave the perfect template for makingsome up." She gestured.

"Reasonable enough, I suppose," hesaid. "But won't they be able to detectour scent beneath it?"

"Trust me," she replied grimly. "We'llspread it on so thick Swizzle himselfwon't recognize us. Even tarsapien nosescan be overwhelmed."

"If you say so." He hesitated. "That'sstill only half of the problem, you know.Human recognition centers on sight, notsmell. Unless Shannon can pull hermiracle off we're still going to haveRom to deal with."

"Yes, well, I've got a couple of ideason that," Kata nodded. "It occurs to methat there's one other human recognitionsystem we might be able to use once wedon't have to worry about the tarsapiens. . . and we've certainly got someonehere who Rom would consider hisenemy. Come on; we can discuss it

while we work on our olfactorycamouflage."

When dawn came, they were ready."Rom?" Shannon called tentatively

through the open door. "Rom, this isShannon. Your wife. Can you hear me?"

Behind her, Mitch shifted his feetsilently, heart thudding in his ears.Artificial tarsapien odor hung thicklyaround them, creating the naggingillusion of being in an especially pungentpeat bog. To tarsapien senses it wouldprobably be overpowering . . . but thathad yet to be tested.

"What do you want?" Rom's voice cutthrough the silence.

"About ten degrees right of the door,"Shannon breathed.

"Got it," Mitch said tersely. "Keephim talking."

Shannon raised her voice again, butMitch didn't wait to hear any more. IfRom stayed put, the window in thegeology lab should offer an exit the othercouldn't see; and if the armed tarsapiensreacted to Kata's concoction like theywere supposed to that end of the forestshould be safe. Should be.

The window made only the faintest ofprotesting squeaks as he unlatched andswung it open, and seconds later he wasstriding quickly across the herbicidering. Behind him he could hear snatchesof the Endurssons' shouted conversationon the far side of the building . . . andwith a feeling akin to having just walked

across the Amazon he reached the edgeof the forest without being shot at. Hetook a moment to let his heartbeat settledown as he checked his bearings on theLostproof. Kata and Lyell had set tentarsapien nets on their last trapping run,and he could only hope the one or twoclosest ones hadn't yet been triggered.Easing the cap off the intravenous dripbottle strapped to his right boot, he madesure it was dribbling its contentsproperly onto the ground and started offaround the circle toward Rom's voice.

In some ways, he discovered quickly,it was more unnerving than the short trekacross open ground had been. Visually,he was certainly better hidden, but theadvantage was almost swallowed up by

the stretches of dry leaves and theoccasional brittle branch underfoot.Besides watching out for suchnoisemakers, he also had to trace out areasonable route and stay alert in caseRom tired of talking with his wife andmoved in his direction. Approximatelyonce per step he reminded himself ofhow crazy this whole plan was.

But Rom's attention remained withShannon, and Mitch penetrated to withinperhaps ten meters before thankfullybeginning a silent retreat in a directionthat would take him deeper into theforest and, ultimately, to the net listed onhis Lostproof.

And a few minutes later he found luckwas indeed with them. The three-meter-

square mesh was still stretched across agap between two trees, waiting like agiant spiderweb for a victim to blunderinto it. It took less than a minute forMitch to complete his job and find ahiding place behind a large sarcaciabush. Raising his communicator, hepunched for Kata. "Ready," he hissed."You?"

"I hope so," she answered, her voicebetraying her own tension. "Mitch . . . ifthis doesn't work—"

"It'll work," he told her. "Come onnow; before Shannon loses him. Thetrail starts between two big ginkgaptrees just opposite the geology labwindow."

"Right. Cross your fingers."

For a minute nothing happened. Allaround him were the normal chirps andclicks of the forest; in the distance hecould just make out Rom's voice. A fewmore minutes, Shannon, he willedsilently. Just let Kata get in position—

"All right," Kata's voice camesuddenly from somewhere betweenMitch and Rom. "You keep saying youwant to kill us?—well, here's yourchance. Come and get me." Mitch hadhalf expected Rom to let loose a bellowlike a charging bull, but nothing like thataccompanied the abrupt sound of bodiescrashing toward him through theundergrowth. His hands tightened aroundhis drawn lightning rod as he tried toguess from the noise whether or not Rom

was gaining. Surely he was alreadyshooting blindly; if any of the needlesconnected—or if he got close enough tosee—

"Promise the others they can leavesafely and I'll stop," Kata's voice came,much closer this time. Rom made noanswer, but as Kata also fell silentMitch found he could now hear thesnick-snick-snick of needles cuttingthrough leaves. They were almost withinsight—he could see movement of lowbranches—

And with a final crash of leavesSwizzle burst into sight, thecommunicator strapped to his backbouncing wildly as he ran for all he wasworth. Mitch caught just a glimpse of

dilated nostrils bare centimeters off theground as the animal followed the trailof jasmine he had carefully laid down;and then the tarsapien veered around thenet and disappeared back into the forest—

Rom, bare seconds behind, had noway of detecting the safe path even ifhe'd known it was there. He hit the net atfull speed, the alien weapon knockedfrom his hand by the impact as the meshwrapped itself solidly about its prey.

Rom didn't bellow this time, either.The sound he made was much more likean anguished scream.

"Well?"Kata sank down into the seat next to

Mitch, gratefully sipping the coffee he'd

poured for her."Uncertain, but hopeful. Adler should

have no problems unless the dart drugcarries something potent in the way ofaftereffects—his body was actuallydoing a reasonable job of eliminating thestuff on its own, though I'm going toleave him on the scrubber another hourto be on the safe side. Rom—" Sheshrugged tiredly. "No way of telling. Wecan keep him sedated or under restraintand try the scrubber when it's free, butwe'll just have to wait and see howfirmly the drug is entrenched in hissystem. I'd hate to keep him tied up untilthe ship comes, but we could do so ifabsolutely necessary."

"Or we could put him in Swizzle's

cage," Mitch offered. "I've got a feelingwe won't be needing it again."

Kata smiled. "Swizzle still eludingyou, eh?"

"Well, we might be able to trap himusing the Sunray but even that's doubtful.On foot, forget it."

"Probably not worth the effort.Besides, we owe him a lot, and maybeletting him go free's the best way to clearthe ledger. I don't think I would haveliked leading Rom into that net inperson." Mitch cocked an eyebrow."Rom's comment about biologistsplaying God really got to you, didn't it?"

"A little," she admitted. "But then, youalready know how much I try to keep myrelationships on an intellectual level. I

suppose that applies to my relationshipswith test subjects, too." He shrugged,looking a bit uncomfortable. "That's howscientists are supposed to be."

"Maybe. But maybe I've just beenusing that as an excuse."

"An excuse for what?"Kata took a deep breath, steeling

herself. This wasn't going to be easy tosay, but it'd been rehearsing itself in theback of her mind for the past hour andshe was determined to let it come out. "Iget the feeling that you were rather upsetby what I said yesterday aboutrelationships fouling up your mind." Hewaved a hand in dismissal. "Forget it.I've always had a tendency to go overlystarry-eyed. Too much City of Night

influence on my early life, I suppose.""Yeah, I noticed. Rushing out there to

rescue Rom and then Adler . . . ." Shesmiled ruefully at the memory. "I don'tthink I'd like to go quite that faroverboard."

"You don't want most of the rest of it,either," Mitch said. "Overly romanticisn't any better for getting close topeople than overly intellectual. I'mforever winding up having my bubblepopped." She shrugged fractionally. Sohe does it, too, she thought. "Yours is amore subtle approach, I'd say, but itseems just as good as my method . . . orRom's or Adler's, for that matter."

"Come again?""Our methods for keeping other

people at a safe arm's reach," sheamplified. "Don't you see? Rom'sbelligerent cynicism, Adler's all-consuming attention to his career—they're just different versions of whatyou and I are doing. We all have ourown—"

"Our own personal cordonssanitaires?" Mitch offered with a wryhalf-smile.

"My words exactly.""It was an obvious metaphor. Sort of

makes sense, I suppose—humangregariousness does have certainboundaries." He looked at her curiously."May I ask what got you started on thisline of thought?" She shrugged again."Oh, I don't know. Probably because

Shannon held up so much better than Iexpected her to. You know; the oldproblem of theory versus reality."

"Besides which, you really didn'tunderstand why she was willing to riskher life for Rom?" Kata felt herselfflush. "I suppose that's part of it," sheadmitted. "Knowledge andunderstanding are supposed to be mystock in trade, after all. Being told I can'tdo something has always bugged me."

"Um." He eyed her, a touch ofwariness in his face. "So now what? Webreak down the barriers and joyfullyembrace in the clear light of the risingsun?"

She chuckled, fully aware that he wasonly half-joking. 'I'm not ready to scrap

my entire cordon sanitaire quite thatfast, thanks. I just thought . . . well, thatmaybe we both ought to start re-thinkinghow we deal with people. Rememberhow hard Shannon said it was for Romto break his antisocial image? I wouldn'twant that kind of rigid attitude getting agrip on me." She hesitated. "Or on you,either," she added with only a littledifficulty.

A twitch at the corner of his mouthshowed he'd caught the smallconcession, but he had the grace not topush it. "Especially one like Rom's," henodded. "That brand of active defensecan be pretty hard on friend or foe. Orinnocent bystander."

Kata looked out the window,

suppressing a shiver. "We'll go lookingfor them, you know, once all this getsout. You think we'll find them?"

"I hope not," Mitch said fervently. "Ifthey could do this on Pallas, who knowswhat they've done to booby-trap theirown system?"

"I don't even want to think about it."