The Year's Best Science Fiction: Fifteenth Annual Collection

by Gardner Dozois

  "Nervous, Marius?"

  "In your hands? Not likely."

  "That's the spirit."

  They bought two mugs of mocha from a nearby servitor, then returned to the ventling display, making what seemed like small-talk. During indoctrination Cholok had been taught phrase-embedded three. The code allowed the insertion of secondary information into a primary conversation, by careful deployment of word-order, hesitation and sentence structure.

  "What have you got?" Vargovic asked.

  "A sample," Cholok answered, one of the easy, preset words which did not need to be laboriously conveyed. But what followed took nearly five minutes to put over, freighted via a series of rambling reminiscences of the Phobos years. "A small shard of hyperdiamond."

  Vargovic nodded. He knew what hyperdiamond was: a topologically complex interweave of tubular fullerene; structurally similar to cellulose or bulk chitin but thousands of times stronger; its rigidity artificially maintained by some piezoelectric trick which Gilgamesh lacked. "Interesting," Vargovic said. "But unfortunately not interesting enough."

  She ordered another mocha and downed it replying. "Use your imagination. Only the Demarchy knows bow to synthesize it."

  "It's also useless as a weapon."

  "Depends. There's an application you should know about."

  "What?"

  "Keeping this city afloat-and I'm not talking about economic solvency. Do you know about Buckminster Fuller? He lived about 400 years ago; believed absolute democracy could be achieved through technological means."

  "The fool."

  "Maybe. But Fuller also invented the geodesic lattice which determines the structure of the buckyball; the closed allotrope of tubular fullerene. The city owes him on two counts."

  "Save the lecture. How does the hyperdiamond come into it?"

  "Flotation bubbles," she said. "Around the outside of the city. Each one is a hundred-metre wide sphere of hyperdiamond, holding vacuum. A hundred-metre wide molecule, in fact, since each sphere is composed of one endless strand of tubular fullerene. Think of that, Marius: a molecule you could park a ship inside."

  While he absorbed that, another part of his mind continued to read the ventling caption; how their biochemistry had many similarities with the gutless tube worms which lived around Earth's ocean vents. The ventlings drank hydrogen sulphide through their funnels, circulating via a modified form of haemoglobin, passing through a bacteria-saturated organ in the lower part of their bags. The bacteria split and oxidized the hydrogen sulphide, manufacturing a molecule similar to glucose. The glucose-analogue nourished the ventling, enabling it to keep living and occasionally make slow perambulations to other parts of the vent, or even to swim between vents, until the adult phase rooted it to the ground. Vargovic read this, and then read it again, because he had just remembered something; a puzzling intercept passed to him from cryptanalysis several months earlier-, something about Demarchy plans to incorporate ventling biochemistry into a larger animal. For a moment he was tempted to ask Cholok about it directly, but he decided to force the subject from his mind until a more suitable time.

  "Any other propaganda to share with me?"

  "There are 200 of these spheres. They inflate and deflate like bladders, maintaining C-A's equilibrium. I'm not sure how the deflation happens, except that it's something to do with changing the piezoelectric current in the tubes."

  "I still don't see why Gilgamesh needs it."

  "Think. If you can get a sample of this to Ganymede, they might be able to find a way of attacking it. All you'd need would be a molecular agent capable of opening the gaps between the fullerene strands so that a molecule of water could squeeze through, or something which impedes the piezoelectric force."

  Absently Vargovic watched a squidlike predator nibble a chunk from the bag of a ventling. The squid blood ran thick with two forms of haemoglobin; one oxygen-bearing, one tuned for hydrogen sulphide. They used glycoproteins to keep their blood flowing and switched metabolisms as they swam from oxygendominated to sulphide-dominated water.

  He snapped his attention back to Cholok. "I can't believe I came all this way for ... what? Carbon?" He shook his head, slotting the gesture into the primary narrative of their conversation. "How did you obtain this?"

  "An accident, with a gilly."

  "Go on."

  "An explosion near one of the bubbles. I was the surgeon assigned to the gilly; had to remove a lot of hyperdiamond from him. It wasn't hard to save a few splinters."

  "Forward thinking of you."

  "Hard part was persuading Gilgamesh to send you. Especially after Maunciple .. ."

  "Don't lose any sleep over him," Vargovic said, consulting his coffee. "He was a fat bastard who couldn't swim fast enough."

  The surgery took place the next day. Vargovic woke with his mouth furnace-dry.

  He felt-odd. They had warned him of this. He had even interviewed subjects who had undergone similar procedures in Gilgamesh's experimental labs. They told him he would feel fragile, as if his head was no longer adequately coupled to his body. The periodic flushes of cold around his neck only served to increase that feeling.

  "You can speak," Cholok said, looming over him in surgeon's whites. "But the cardiovascular modifications-and the amount of reworking we've done to your laryngeal area-will make your voice sound a little strange. Some of the gilled are really only comfortable talking to their own kind."

  He held a hand before his eyes, examining the translucent webbing which now spanned his fingers. There was a dark patch in the pale tissue of his palm: Cholok's embedded sample. The other hand held another.

  "It worked, didn't it?" His voice sounded squeaky. "I can breathe water."

  "And air," Cholok said. "Though what you'll now find is that really strenuous exercise only feels natural when you're submerged."

  "Can I move?"

  "Of course," she said. "Try standing up. You're stronger than you feel."

  He did as she suggested, using the moment to assess his surroundings. A neural monitor clamped his crown. He was naked, in a brightly lit revival room; one glass-walled side facing the exterior ocean. It was from here that Cholok had first contacted Gilgamesh.

  "This place is secure, isn't it?"

  "Secure?" she said, as if it was obscene. "Yes, I suppose so."

  "Then tell me about the Denizens."

  "What?"

  "Demarchy code word. Cryptanalysis intercepted it recently-supposedly something about an experiment in radical biomodification. I was reminded of it in the aquarium." Vargovic fingered the gills in his neck. "Something that would make this look like cosmetic surgery. We heard the Demarchy had tailored the sulphur-based metabolism of the ventlings for human use."

  She whistled. "That would be quite a trick."

  "Useful, though-especially if you wanted a work force who could tolerate the anoxic environments around the vents, where the Demarchy happens to have certain mineralogical interests."

  "Maybe." Cholok paused. "But the changes required would be beyond surgery. You'd have to script them in at the developmental level. And even then ... I'm not sure what you'd end up with would necessarily be human any more." It was as if she shivered, though Vargovic was the one who felt cold, still standing naked beside the revival table. "All I can say is, if it happened, no one told me."

  "I thought I'd ask, that's all."

  "Good." She brandished a white medical scanner. "Now can I run a few more tests? We have to follow procedure."

  Cholok was right: quite apart from the fact that Vargovic's operation was completely real-and therefore susceptible to complications which had to be looked for and monitored-any deviation from normal practise was undesirable.

  After the first hour or so, the real strangeness of his transformation hit home. He had been blithely unaffected by it until then, but when he saw himself in a full-body mirror, in the corner of Cholok's revival room, he knew that there was no going back.

  Not easily, anyway. The Gi
lgamesh surgeons had promised him they could undo the work-but he didn't believe them. After all, the Demarchy was ahead of Ganymede in the biosciences, and even Cholok had told him reversals were tricky. He'd accepted the mission in any case: the pay tantalizing; the prospect of the sulphur projects rather less.

  Cholok spent most of the day with him, only breaking off to talk to other clients or confer with her team. Breathing exercises occupied most of that time: prolonged periods spent underwater, nulling the brain's drowning response. Unpleasant, but Vargovic had done worse things in training. They practised fully submerged swimming, using his lungs to regulate buoyancy, followed by instruction about keeping his gill-openings-what Cholok called his opercula-clean, which meant ensuring the health of the colonies of commensal bacteria which thrived in the openings and crawled over the fine secondary flaps of his lamellae. He'd read the brochure: what she'd done was to surgically sculpt his anatomy toward a state somewhere between human and air-breathing fish: incorporating biochemical lessons from lungfish and walking-catfish. Fish breathed water through their mouths and returned it to the sea via their gills, but it was the gills in Vargovic's neck which served the function of a mouth. His true gills were below his thoracic cavity; crescent-shaped gashes below his ribs.

  "Compared to your body size," she said, "these gill-openings are never going to give you the respiratory efficiency you'd have if you went in for more dramatic changes ..."

  "Like a Denizen?"

  "I told you, I don't know anything."

  "It doesn't matter." He flattened the gill-flaps down, watching-only slightly nauseated-as they puckered with each exhalation. "Are we finished?"

  "Just some final bloodwork," she said. "To make sure everything's still working. Then you can go and swim with the fishes." While she was busy at one of her consoles, surrounded by false-colour entoptics of his gullet-be asked her: "Do you have the weapon?"

  Cholok nodded absently and opened a drawer, fishing out a hand-held medical laser. "Not much," she said. "I disabled the yield-suppresser, but you'd have to aim it at someone's eyes to do much damage."

  Vargovic hefted the laser, scrutinizing the controls in its contoured haft. Then he grabbed Cholok's bead and twisted her around, dousing her face with the laser's actinic-blue beam. There were two consecutive popping sounds as her eyeballs evaporated. "What, like that?"

  Conventional scalpels did the rest.

  He rinsed the blood, dressed and left the medical centre alone, travelling kilometres down-city, to where Cadmus-Asterius narrowed to a point. Even though there were many gillies moving freely through the city-they were volunteers, by and large, with full Demarchy rights-he did not linger in public for long. Within a few minutes he was safe within a warren of collagen-walled service tunnels, frequented only by technicians, servitors or other gill-workers. The late Cholok had been right; breathing air was harder now; it felt too thin.

  "Demarchy security advisory," said a bleak machine voice emanating from the wall. "A murder has occurred in the medical sector. The suspect may be an armed gill-worker. Approach with extreme caution."

  They'd found Cholok. Risky, killing her. But Gilgamesh preferred to burn its bridges, removing the possibility of any sleeper turning traitor after they had fulfilled their usefulness. In the future, Vargovic mulled, they might be better using a toxin, rather than the immediate kill. He made a mental note to insert this in his report.

  He entered the final tunnel, not far from the waterlock which had been his destination. At the tunnel's far end a technician sat on a crate, listening with a stethoscope to something going on behind an access panel. For a moment Vargovic considered passing the man, hoping he was engrossed in his work. He began to approach him, padding on bare webbed feet, which made less noise than the shoes he had just removed. Then the man nodded to himself, uncoupled from the listening post and slammed the hatch. Grabbing his crate, he stood and made eye contact with Vargovic.

  "You're not meant to be here," he said. Then offered, almost plaintively: "Can I help you? You've just had surgery, haven't you? I always know the ones like you: always a little red around the gills."

  Vargovic drew his collar higher, then relented because that made it harder to breathe. "Stay where you are," he said. "Put down the crate and freeze."

  "Christ, it was you, wasn't it-that advisory?" the man said.

  Vargovic raised the laser. Blinded, the man blundered into the wall, dropping the crate. He made a pitiful moan. Vargovic crept closer, the mall stumblg into the scalpel. Not the cleanest of killings, but that hardly mattered.

  Vargovic was sure the Demarchy would shortly seal off access to the ocean especially when his last murder came to light. For now, however, the locks were accessible. He moved into the air-filled chamber, his lungs now aflame for water. High-pressure jets filled the room, and he quickly transitioned to waterbreathing, feeling his thoughts clarify. The secondary door clammed open, revealing ocean. He was kilometres below the ice, and the water here was both chillingly cold and under crushing pressure-but it felt normal; pressure and cold registering only as abstract qualities of the environment. His blood was inoculated with glycoproteins now; molecules which would lower its freezing point below that of water.

  The late Cholok had done well.

  Vargovic was about to leave the city when a second gill-worker appeared in the doorway, returning to the city after completing a shift. He killed her efficiently, and she bequeathed him a thermally inwoven wet suit, for working in the coldest parts of the ocean. The wet suit had octopus ancestry, and when it slithered onto him it left apertures for his gill-openings. She had been wearing goggles which had infrared and sonar capability, and carried a hand-held tug. The thing resembled the still-beating heart of a vivisected animal, its translucent components knobbed with dark veins and ganglia. But it was easy to use: Vargovic set its pump to maximum thrust and powered away from the lower levels of C-A.

  Even in the relatively uncontaminated water of the Europan ocean, visibility was low; he would not have been able to see anything were the city not abundantly illuminated on all its levels. Even so, he could see no more than half a kilometer upwards; the higher parts of C-A lost in golden haze and then deepening darkness. Although its symmetry was upset by protrusions and accretions, the city's basic come form was evident, tapering at the narrowest point to an inlet mouth which ingested ocean. The cone was surrounded by a haze of flotation bubbles, black as caviar. He remembered the chips of hyperdiamond in his hands. If Cholok was right, Vargovic's people might find a way to make it waterpermeable; opening the fullerene weave sufficiently so that the spheres' buoyant properties would be destroyed. The necessary agent could be introduced into the ocean by ice-penetrating missiles. Some time later-Vargovic was uninterested in the details-the Demarchy cities would begin to groan under their own weight. If the weapon worked sufficiently quickly, there might not even be time to act against it. The cities would fall from the ice, sinking down through the black kilometres of ocean below them. He swam on.

  Near C-A, the rocky interior of Europa climbed upwards to meet him. He had travelled three or four kilometres north, and was comparing the visible topography-lit by service lights installed by Demarchy gill-workers-with his own mental maps of the area. Eventually he found an outcropping of silicate rock. Beneath the overhang was a narrow ledge, on which a dozen or so small boulders had fallen. One was redder than the others. Vargovic anchored himself to the ledge and hefted the red rock, the warmth of his fingertips activating its latent biocircuitry. A screen appeared in the rock, filling with the face of Mishenka.

  "I'm on time," Vargovic said, his own voice sounding even less recognizable through the distorting medium of the water. "I presume you're ready?"

  "Problem," Mishenka said. "Big fucking problem."

  "What?"

  "Extraction site's compromised." Mishenka-or rather the simulation of Mishenka which was running in the rock-anticipated Vargovic's next question: "A few hours ago the Demarc
hy sent a surface team out onto the ice, ostensibly to repair a transponder. But the spot they're covering is right where we planned to pull you out." He paused. "You did-uh-kill Cholok, didn't you? I mean you didn't just grievously injure her?"

  "You're talking to a professional."

  The rock did a creditable impression of Mishenka looking pained. "Then the Demarchy got to her."

  Vargovic waved his hand in front of the rock. "I got what I came for, didn't I?"

  "You got something."

  "If it isn't what Cholok said it was, then she's accomplished nothing except get herself dead."

  "Even so .. ." Mishenka appeared to entertain a thought briefly, before discarding it. "Listen, we always had a backup extraction point, Vargovic. You'd better get your ass there." He grinned. "Hope you can swim faster than Maunciple."

  It was 30 kilometres south.

  He passed a few gill-workers on the way, but they ignored him and once he was more than five kilometres from C-A there was increasingly less evidence of human presence. There was a head-up display in the goggles. Vargovic experimented with the readout modes before calling up a map of the whole area. It showed his location, and also three dots which were following him from C-A.

  He was being tailed by Demarchy security.

  They were at least three kilometres behind him now, but they were perceptibly narrowing the distance. With a cold feeling gripping his gut, it occurred to Vargovic that there was no way he could make it to the extraction point before the Demarchy caught him.

  Ahead, he noticed a thermal hot-spot; heat bubbling up from the relatively shallow level of the rock floor. The security operatives were probably tracking him via the gill-worker's appropriated equipment. But once he was near the vent he could ditch it: the water was warmer there; he wouldn't need the suit, and the heat, light and associated turbulence would confuse any other tracking system. He could lie low behind a convenient rock, stalk the while they were preoccupied with the homing signal. It struck Vargovic as a good plan.

  He made the distance to the vent quickly, feeling the water warm around him, noticing how the taste of it changed; turning brackish. The vent was a fiery red fountain surrounded by bacteria-crusted rocks and the colourless Europan equivalent of coral. Ventlings were everywhere; their pulpy bags shifting as the currents altered. The smallest were motile, ambling on their stilts like animated bagpipes, navigating around the triadic stumps of their dead relatives.