"Yeah," grumpily. "Digger Command makes the record book for longest sustained operations, but the Tiefers gained by quitting just when they did." He sighed and said something that might have gotten him cashiered in other circumstances, but when you're five years past the end of the world, there aren't a lot of people to hear. "You know, the Tiefers aren't such a bad sort. Take the long view and you'll see nastier types in some of our own allies, waiting for Crown and Tiefstadt to beat each other into a bloody pulp. That's the place where we should be doing our planning, for the next baddies that are going to come after us. We're going to win this war, but if we have to win it with the tunnels and the Diggers, we'll still be fighting for years into the New Sun."

He gave his aromatique an emphatic crunch and jabbed a forehand at Smith. "Your project is our only chance to bring this to a clean end."

Smith's reply was abrupt. "And the chances would have been still better if you had let me stay with the Team."

Greenval seemed to ignore the complaint. "Victory, you've been with this project for seven years now. Do you really think it can work?"

Maybe it was the stale air, making them all daft. Indecision was totally alien to the public image of Strut Greenval. She had known him for nine years. Among his closest confidants, Greenval was an open-minded person-up to the point where final decisions had to be made. Then he was the man without doubt, facing down ranks of generals and even the King's political advisors. Never had she heard such a sad, lost question coming from him. Now she saw an old, old man who in a few hours would surrender to the Dark, perhaps for the last time. The realization was like leaning against a familiar railing and feeling it begin to give way. "S-sir, we have selected our targets well. If they are destroyed, Tiefstadt's surrender should follow almost immediately. Underhill's Team is in a lake less than two miles from the targets." And that was an enormous achievement in itself. The lake was near Tiefstadt's most important supply center, a hundred miles deep in Tiefer territory.

"Unnerby and Underhill and the others need only walk a short distance, sir. We tested their suits and the exotherms for much longer periods in conditions almost as-"

Greenval smiled weakly. "Yes, I know. I jammed the numbers down the craw of the General Staff often enough. But now we're really going to do it. Think what that means. Over the last few generations, we military types have done our little desecrations around the edges of the Dark. But Unnerby's team will see the center of the Deepest Dark. What can that really be like? Yes, we think we know: the frozen air, the vacuum. But that's all guesses. I'm not religious, Colonel Smith, but...I wonder at what they may find."

Religious or not, all the ancient superstitions of snow-trolls and earth-angels seemed to hover just behind the general's words. Even the most rational quailed before the thought of a Dark so intense that in a sense the world did not exist. With an effort, Victory ignored the emotions that Greenval's words conjured. "Yes, sir, there could be surprises. And I'd rate this scheme as a likely failure, except for one thing: Sherkaner Underhill."

"Our pet screwball."

"Yes, a screwball of a most extraordinary sort. I've known him for seven years-ever since that afternoon he showed up with a car full of half-made prototypes and a head full of crazy schemes. Lucky for us I was having a slow afternoon. I had time to listen and be amused. The average academic type comes up with maybe twenty ideas in a lifetime. Underhill has twenty an hour; it's almost like a palsy with him. But I've known people almost as extreme in Intelligence school. The difference is that Underhill's ideas are feasible about one percent of the time-and he can tell the good ones from the bad with some accuracy. Maybe someone else would have thought of using swamp sludge to breed the exotherms. Certainly someone else could have had his ideas about airsuits. But he has the ideas and he brings them together, and they work.

"But that's only part of it. Without Sherkaner, we could not have come close to implementing all we have in these last seven years. He has the magic ability to rope bright people into his schemes." She remembered Hrunkner Unnerby's angry contempt that first afternoon, how it had changed over a period of days until Hrunkner's engineering imagination was totally swept up by the ideas Sherkaner was spewing at him. "In a sense, Underhill has no patience for details, but that doesn't matter. He generates an entourage which does. He's just...remarkable."

This was all old news to both of them; Greenval had argued similarly to his own bosses over the years. But it was the best reassurance Victory could give the old cobber now. Greenval smiled and his look was strange. "So why didn't you marry him, Colonel?"

Smith hadn't meant that to come up, but hell, they were alone, and at the end of the world: "I intend to, sir. But there's a war on, and you know I'm...not much for tradition; we'll marry after the Dark." It had taken Victory Smith just one afternoon to realize that Underhill was the strangest person she had ever met. It had taken her another couple of days to realize he was a genius who could be used like a dynamo, could be used to literally change the course of a world war. Within fifty days she had had Strut Greenval convinced of the same, and Underhill was tucked away in his own lab, with labs growing up around him to handle the peripheral needs of the project. Between her own missions, Victory had schemed on how she might claim the Underhill phenomenon-that was how she thought of him, how the Intelligence Staff thought of him-as her permanent advantage. Marriage was the obvious move. A traditional Marriage-in-the-Waning would have suited her career path. It all would have been perfect, except for Sherkaner Underhill himself. Sherk was a person with his own plans. Ultimately he had become her best friend, as much someone to scheme with as to scheme about. Sherk had plans for after the Dark, things that Victory had never repeated to anyone. Her few other friends-even Hrunkner Unnerby-liked her despite her being out-of-phase. Sherkaner Underhill actually liked the idea of out-of-phase children. It was the first time in her life that Victory had met with more than mere acceptance. So for now they fought a war. If they both survived, there was another world of plans and a life together, after the Dark.

And Strut Greenval was clever enough to figure out a lot of this. Abruptly, she glared at her boss. "You already knew, didn't you? That's why you wouldn't let me stay with the Team. You figure it's a suicide mission, and my judgment would be warped... Well it is dangerous, but you don't understand Sherkaner Underhill; self-sacrifice is not on his agenda. By our standards he's rather a coward. He's not especially taken by most of the things you and I hold dear. He's risking his life out of simple curiosity-but he's very, very careful when it comes to his own safety. I think the Team will succeed and survive. The odds would only have been improved if you'd let me stay with them! Sir."

Her last words were punctuated by the dramatic dimming of the room's single lamp. "Hah," said Greenval, "we've been without fuel oil for twelve hours, did you know that, Colonel? Now the lead acid batteries have about run down. In a couple of minutes Captain Diredr will be here with the Last Word from maintenance: 'Begging your pardon, sir, but the last pools will freeze momentarily. Engineering begs that you join them for final shutdown.'" He mimicked his aide's high-pitched voice.

Greenval stood, leaned across the desk. His doubts were hidden once more, and the old snap was back in his manner. "In that time, I want to clear up a few things about your orders and your future. Yes, I brought you back because I don't want to risk you on this mission. Your Sergeant Unnerby and I have had some long talks. We've had nine years to put you through almost limitless risk, and to watch how your mind works when thousands of lives depend on the right answers. It's time to take you off the front lines of special operations. You are one of the youngest colonels in modern times; after this Dark, you'll be the youngest general."

"Only if the Underhill mission succeeds."

"Don't interrupt. However the Underhill affair goes, the King's advisors know how good you are. Whether or not I survive this Dark, you'll be sitting in my job within a few years of the starting of the New Sun-and your days of personal risk-taking must be over. If your Mr. Underhill survives, marry him, breed him, I couldn't care less. But never ever again are you to put yourself at risk." He waved his pointed hand at her head, a mock threat with an edge. "If you do, I swear I'll come back from the grave and crack your thick shell."

There was the sound of footsteps in the narrow hallway. Hands scratched at the heavy curtain that was the room's only door. It was Captain Diredr. "Excuse me, General. Engineering is absolutely insistent, sir. We have thirty minutes of electrical power, at the outside. They are begging, sir-"

Greenval spat that last aromatique into a stained cuspidor. "Very good, Captain. We are coming down instanter." He sidled around the Colonel, and pulled back the curtain. When Smith hesitated to go before him, he waved her through the doorway. "In this case, senior means last, my dear. I've never liked this business of cheating on the Dark, but if we have to do it, I'm the one who gets to turn out the lights!"

SEVEN.

By rights Pham Trinli should not have been on the Fleet Captain's bridge, certainly not during a serious operation. The old man sat at one of the duplicate comm posts, but he really didn't do anything with it. Trinli was Programmer-at-Arms 3rd, though no one had ever seen him behave productively, even at that low rank. He seemed to come and go at his own pleasure, and spent most of his time down in the employees' dayroom. Fleet Captain Park was known to be a little irrational when it came to "respect for age." Apparently, as long as Pham Trinli did no harm, he could stay on the payroll.

Just now, Trinli sat half-turned away from his post. He listened dyspeptically to the quiet conversations, the flow of check and response. He looked past the techs and armsmen at the common displays.

The landings of Qeng Ho and Emergent vessels had been a dance of caution. Mistrust for the Emergents extended from top to bottom among Captain Park's people. Thus there were no combined crews, and the comm nets were fully duplicated. Captain Park had positioned his capital vessels in three groups, each responsible for a third of the planetary operations. Every Emergent ship, every lander, every free-flying crewman was monitored for evidence of treachery.

The bridge's consensus imagery showed most of this. Relayed from the "eastern" cluster, Trinli could see a trio of Emergent heavy lifters coming off the frozen surface of the ocean, towing between them a quarter-million-tonne block of ice. That was the sixth lift in this op. The surface was brightly lit by the rocket glare. Trinli could see a hole hundreds of meters deep. Steaming froth masked the gouge in the seafloor. Soundings showed there were plenty of heavy metals in this section of continental shelf, and they were mining it with the same brute force that they employed when they carved the ice.

Nothing really suspicious there, though things may change when it comes time to divvy up the loot.

He studied at the comm status windows. Both sides had agreed to broadcast intership communications in the clear; a number of Emergent specialists were in constant conference comm with corresponding Qeng Ho officers; the other side was sucking in everything they could about Diem's discoveries in the dry valley. Interesting how the Emergents suggested simply grabbing the native artifacts. Very un-Qeng-Ho-like. More like something I might do.

Park had dumped most of his fleet's microsats into near-planetary space just before the Emergents arrived. There were tens of thousands of the fist-sized gadgets out there now. Subtly maneuvering, they came between the Emergents' vehicles far more often than simple chance would predict. And they reported back to the electronic intelligence window here on the bridge. They reported that there was far too much line-of-sight talk between the Emergent vessels. It might be innocent automation. More likely it was cover for encrypted military coordination, sly preparation on the part of the enemy. (And Pham Trinli had never thought of the Emergents as anything but an enemy.) Park's staff recognized the signs, of course. In their prissy way, these Qeng Ho armsmen were very sharp. Trinli watched three of them argue about the broadcast patterns that washed across the fleet from Emergent emitters. One of the junior armsmen thought they might be seeing a mix of physical-layer and software probing-all in an orchestrated tangle. But if that were true, it was more sophisticated than the Qeng Ho's own best e-measures...and that was unbelievable. The senior armsman just frowned at the junior, as if the suggestion were a king-sized headache. Even the ones who have been in combat don't get the point. For a moment, Trinli's expression got even more sour.

A voice sounded privately in his ear. "What do you think, Pham?"

Trinli sighed. He mumbled back into his comm, his lips barely moving, "It stinks, Sammy. You know that."

"I'd feel better if you were at an alternate control center." The Pham Nuwen's "bridge" had this official location, but in fact there were control centers distributed throughout the ship's livable spaces. More than half the staff visible on the bridge were really elsewhere. In theory, it made the starship a tougher kill. In theory.

"I can do better than that. I've hacked one of the taxis for remote command." The old man floated off his saddle. He drifted silently behind the ranks of the bridge technicians, past the view on the heavy lifters, the view of Diem's crew preparing to lift off from the dry valley, the images of oh-so-intent Emergent faces...past the ominous e-measures displays. No one really noticed his passage, except that as he slid through the bridge entranceway, Sammy Park glanced at him. Trinli gave the Fleet Captain a little nod.

Spineless wretches, nearly every one. Only Sammy and Kira Pen Lisolet had understood the need to strike first. And they had not persuaded a single member of the Trading Committee. Even after meeting the Emergents face-to-face, the committee couldn't recognize the other side's certain treachery. Instead, they asked a Vinh to decide for them. A Vinh!

Trinli coasted down empty corridors, slowed to a stop by the taxi lock, and popped the hatch on the one he had specially prepared. I could ask Lisolet to mutiny. The Deputy Fleet Captain had her own command, the QHS Invisible Hand. A mutiny was physically possible, and once she started shooting, Sammy and the others would surely have to join her.

He slipped into the taxi, started the lock pumps. No, I wash my hands of all of them. Somewhere at the back of his skull, a little headache was growing. Tension didn't usually affect him this way. He shook his head. Okay, the truth was, he wasn't asking Lisolet to mutiny, because she was one of those very rare people who had honor. So, he would do the best with what he had. Sammy had brought weapons. Trinli grinned, anticipating the time ahead. Even if the other side strikes first, I wager we're the last men standing. As his taxi drifted out from the Qeng Ho flagship, Trinli studied the threat updates, planning. What would the other side try? If they waited long enough, he might yet figure out Sammy's weapons locks...and be his own one-man mutiny.

There were plenty of signs of the treachery abuilding, but even Pham Trinli missed the most blatant. You had to guess the method of attack to recognize that one.

Ezr Vinh was quite ignorant of military developments overhead. The Ksecs spent on the surface had been hard, fascinating work, work that didn't leave much time to pursue suspicions. In all his life, he had spent only a few dozen Msecs walking around on the surface of planets. Despite exercise and Qeng Ho medicine, he was feeling the strain. The first Ksecs had seemed relatively easy, but now every muscle ached. Fortunately, he wasn't the only wimp. The whole crew seemed to be dragging. Final cleanup was an eternity of careful checking that they had left no garbage, that any signs of their presence would be lost in the effects of OnOff's relighting. Crewleader Diem twisted his ankle on the climb back to the lander. Without the freight winch on the lander, the rest of the climb would have been impossible. When they finally got aboard, even stripping off and stowing their thermal jackets was a pain.

"Lord." Benny collapsed on the rack next to Vinh. There were groans from all along the aisle as the lander boosted them skyward. Still, Vinh felt a quiet glow of satisfaction; the fleet had learned far more from their one landing than anyone expected. Theirs was a righteous fatigue.

There was little chitchat among Diem's crewmembers now. The sound of the lander's torch was an almost subsonic drone that seemed to originate in their bones and grow outward. Vinh could still hear public conversations from on high, but Trixia was out of it. No one was talking to Diem's people now. Correction: Qiwi was trying to talk to him, but Ezr was just too tired to humor the Brat.

Over the curve of the world, the heavy lifting was behind schedule. Clean nukes had broken up several million tonnes of frozen ocean, but steam above the extraction site was complicating the remainder of the job. The Emergent, Brughel, was complaining that they had lost contact with one of their lifters.

"I think it's your angle of view, sir," came the voice of a Qeng Ho tech. "We can see all of them. Three are still at the surface; one is heavily obscured by the local haze, but it looks well positioned. Three more are in ascent, clean lifts, well separated... One moment..." Seconds passed. On a more "distant" channel, a voice was talking about some sort of medical problem; apparently someone had committed a zero-gee barf. Then the flight controller was back: "That's strange. We've lost our view of the East Coast operation."

Brughel, his voice sharpening: "Surely you have secondaries?"

The Qeng Ho tech did not reply.

A third voice: "We just got an EM pulse. I thought you people were done with your surface blasting?"

"We are!" Brughel was indignant.

"Well we just got three more pulses. I-Yessir!"

EM pulses? Vinh struggled to sit up, but the acceleration was too much, and suddenly his head hurt even more than ever. Say something more, damn it! But the fellow who just said "yessir"-a Qeng Ho armsman by the sound of him-was off the air, or more likely had changed mode and encrypted himself.

The Emergent's voice was clipped and angry: "I want to talk to someone in authority. Now. We know targeting lasers when they shine on us! Turn them off or we'll all regret it."

Ezr's head-up display went clear, and he was looking at the lander's bulkheads. The wallpaper backup flickered on, but the video was some random emergency-procedures sequence.

"Shit!" It was Jimmy Diem. At the front of the cabin, the crewleader was pounding on a command console. Somewhere behind Vinh there was the sound of vomiting. It was like one of those nightmares where everything goes nuts at once.

At that instant, the lander reached end-of-burn. In the space of three seconds, the terrible pressure eased off Vinh's chest and there was the comforting familiarity of zero gee. He pulled on his couch release and coasted forward to Diem.

From the ceiling it was easy to stand with his head by Diem's and see the emergency displays, without getting in the crewleader's way. "We're really shooting at them?" Lord, but my head hurts! When he tried to read Diem's command console, the glyphs swam before his eyes.

Diem turned his head a fraction to look at Ezr. Agony was clear in his face; he could barely move. "I don't know what we're doing. I've lost consensual imaging. Tie yourself down..." He leaned forward as though to focus on the display. "The fleet net has gone hard crypto, and we're stuck at the least secure level," which meant that they would get little information beyond direct commands from Park's armsmen.

The ceiling gave Vinh a solid whack on the butt, and he started to slide toward the back of the cabin. The lander was turning, some kind of emergency override-the autopilot had given no warning. Most likely, fleet command was prepping them for another burn. He tied down behind Diem, just as the lander's main torch lit off at about a tenth of a gee. "They're moving us to a lower orbit...but I don't see anything coming to rendezvous," said Diem. He poked awkwardly at the password field beneath the display. "Okay, I'm doing my own snooping... I hope Park isn't too pissed..."

Behind them, there was the sound of more vomiting. Diem started to turn his head, winced. "You're the mobile one, Vinh. Take care of that."

Ezr slid down the aisle's ladderline, letting the one-tenth-gee load do the moving for him. Qeng Ho lived their lives under varying accelerations. Medicine and good breeding made orientation sickness a rare thing among them. But Tsufe Do and Pham Patil had both upchucked, and Benny Wen was curled up as far as his ties would permit. He held the sides of his head and swayed in apparent agony. "The pressure, the pressure..."

Vinh eased next to Patil and Do, gently vac'd the goo that was dribbling down their coveralls. Tsufe looked up at him, embarrassment in her eyes. "Never barfed in my life."

"It's not you," said Vinh, and tried to think past the pain that squeezed harder and harder. Stupid, stupid, stupid. How could it take so long to understand? It was not the Qeng Ho that was attacking the Emergents; somehow it was quite the reverse.

Suddenly he could see outside again. "I got local consensus," Diem's voice came in his earphones. The crewleader's words came in short, tortured bursts. "Five high-gee bombs from Emergent positions... Target: Park's flag..."

Vinh leaned across the row of couches and looked out. The missiles' jets were pointing away from the lander's viewpoint; the five were faint stars moving faster and faster across the sky, closing on the QHS Pham Nuwen. Yet their paths were not smooth arcs. There were sharp bends and wobbles.

"We must be lasing at them. They're jinking."

One of the tiny lights vanished. "We got one! We-"

Four points of light blazed in the sky. The brightness grew and grew, a thousand times brighter than the faded disk of the sun.

Then the view was gone again. The cabin lights died, winked back on, died again. The bottommost emergency system came online. There was a faint network of reddish lines, outlining equipment bays, airlock, the emergency console. The system was rad-hardened but very simpleminded and low-powered. There wasn't even backup video.

"What about Park's flagship, Crewleader?" asked Vinh. Four close-set detonations, so terribly bright-the corners of a regular tetrahedron, clasping its victim. The view was gone but it would burn in his memory forever. "Jimmy!" Vinh screamed at the front of the cabin. "What about the Pham Nuwen?" The red emergency lights seemed to sway around him; the shouting brought him close to blacking out.

Then Diem's voice came hoarse and loud. "I...I think it's g-gone." Fried, vaped, none of the masking words were easy anymore. "I don't have anything now, but the four nukes...Lord, they were right on top of him!"

Several other voices interrupted, but they were even weaker than Jimmy Diem's. As Vinh started back up the line toward him, the one-tenth-gee burn ended. Without light or brains, what was the lander but a dark coffin? For the first time in his life, Ezr Vinh felt the groundsider's disorienting terror: zero gee could mean they had reached designated orbit, or that they were falling in a ballistic arc that intersected the planet's surface...

Vinh clamped down on his terror and coasted forward. They could use the emergency console. They could listen for word. They could use the local autopilot to fly to the surviving Qeng Ho forces. The pain in his head grew beyond anything Ezr Vinh had ever known. The little red emergency lights seemed to get dimmer and dimmer. He felt his consciousness squeezing down, and the panic rose and choked him. There was nothing he could do.

And just before things all went away, fate showed him one kindness, a memory: Trixia Bonsol had not been aboard the Pham Nuwen.

EIGHT.

For more than two hundred years, the clock mechanism beneath the frozen lake had faithfully advanced itself, exhausting the tension of spring coil after spring coil. The mechanism ticked reliably down through the last spring...and jammed on a fleck of airsnow in the final trigger. There it might have hung until the coming of the new sun, if not for certain other unforeseen events: On the seventh day of the two-hundred-and-ninth year, a series of sharp earthquakes spread outward from the frozen sea, jolting loose the final trigger. A piston slid a froth of organic sludge into a tank of frozen air. Nothing happened for several minutes. Then a glow spread through the organics, temperatures rose past the vapor points of oxygen and nitrogen, and even carbon dioxide. The exhalation of a trillion budding exotherms melted the ice above the little vehicle. The ascent to the surface had begun.

Coming awake from the Dark was not like waking from an ordinary sleep. A thousand poets had written about the moment and-in recent eras-ten thousand academics had studied it. This was the second time that Sherkaner Underhill had experienced it (but the first time didn't really count, since that memory was mixed with the vague memories of babyhood, of clinging to his father's back in the pools of the Mountroyal Deepness).

Coming awake from the Dark was done in pieces. Vision, touch, hearing. Memory, recognition, thought. Did they happen first one and then another and another? Or did they happen all at once, but with the parts not communicating? Where did "mind" begin from all the pieces? The questions would rattle around in Sherkaner's imagination for all of his life, the basis for his ultimate quest... But in those moments of fragmented consciousness, they coexisted with things that seemed much more important: bringing self together; remembering who he was, why he was here, and what had to be done right now to survive. The instincts of a million years were in the driver's perch.

Time passed and thought coalesced and Sherkaner Underhill looked out his vessel's cracked window into the darkness. There was motion-roiling steam? No, more like a veil of crystals swirling in the dim light they floated on.

Someone was bumping his right shoulders, calling his name again and again. Sherkaner pieced together memories. "Yes, Sergeant, I'm away...I mean, awake."

"Excellent." Unnerby's voice was tinny. "Are you injured? You know the drill."

Sherkaner dutifully wiggled his legs. They all hurt; that was a good start. Midhands, forehands, eating hands. "Not sure I can feel my right mid and fore. Maybe they're stuck together."

"Yeah. Probably still frozen."

"How are Gil and Amber?"

"I'm talking to them on the other cables. You're the last one to get his head together, but they've got bigger hunks of body still frozen."

"Gimme the cable head." Unnerby passed him the sound-conducting gear, and Sherkaner talked directly to the other Team members. The body can tolerate a lot of differential thawing, but if the process doesn't complete, rot sets in. The problem here was that the bags of exotherm and fuel had shifted around as the boat melted its way to the surface. Sherkaner reset the bags and started sludge and air flowing through them. The green glow within their tiny hull brightened, and Sherkaner took advantage of the light to check for punctures in their breathing tubes. The exotherms were essential for heat, but if the Team had to compete with them for oxygen the Team would be the dead loser.

A half hour passed, the warmth enveloping them, freeing their limbs. The only frost damage was at the tips of Gil Haven's midhands. That was a better safety record than most deepnesses. A broad smile spread across Sherkaner's aspect. They had made it, wakened themselves in the Deep of the Dark.

The four rested a while longer, monitoring the airflow, exercising Sherkaner's scheme for controlling the exotherms. Unnerby and Amberdon Nizhnimor went through the detailed checklist, passing suspicious and broken items across to Sherkaner. Nizhnimor, Haven, and Unnerby were very bright people, a chemist and two engineers. But they were also combat professionals. Sherkaner found fascinating the change that came over them when they moved out of the lab and into the field. Unnerby especially was such a layering: hardbitten soldier atop imaginative engineer, hiding a traditional, straitlaced morality. Sherkaner had known the sergeant for seven years now. The fellow's initial contempt for Underhill schemes was long past; they had been close friends. But when their Team finally moved to the Eastern Front, his manner had become distant. He had begun to address Underhill as "sir," and sometimes his respectfulness was edged with impatience.

He'd asked Victory about that. It had been the last time they were alone together, in a cold burrow-barracks beneath the last operating aerodrome on the Eastern Front. She had laughed at the question. "Ah, dear soft one, what do you expect? Hrunk will have operational command once the Team leaves friendly territory. You are the civilian advisor with no military training, who must somehow be tucked into the chain of command. He needs your instant obedience, but also your imagination and flexibility." She laughed softly; only a curtain separated their conversation from the main hall of the narrow barracks. "If you were an ordinary recruit, Unnerby would have fried your shell half a dozen times by now. The poor cobber is so afraid that when seconds count, your genius will be caught on something completely irrelevant-astronomy, whatever."

"Um." Actually, he had wondered how the stars might look without the atmosphere to dim their colors. "I see what you mean. Put that way, I'm surprised he let Greenval put me on the Team."

"Are you kidding? Hrunk demanded you be on it. He knows there'll be surprises that only you can figure out. As I said; he's a cobber with a problem."

It wasn't often that Sherkaner Underhill felt taken aback, but this was one of those times. "Well, I'll be good."

"Yes, I know you will. I just wanted you to know what Hrunk is up against... Hey, you can look on it as a behavioral mystery: How can such radically crazy people cooperate and survive where no one has ever lived before?" Maybe she meant it as a joke, but it was an interesting question.

Without doubt, their vehicle was the strangest in all history: part submarine, part portable deepness, part sludge bucket. Now the fifteen-foot shell rested in a shallow pool of glowing green and tepid-red. The water was in a vacuum boil, gases swirling up from it, chilling into tiny crystals, and falling back. Unnerby pushed open the hatch, and the team formed a chain, handing equipment and exotherm tanks from one to the next to the next, until the ground just beyond the pool was piled with the gear they would carry.

They strung audio cable between themselves, Underhill to Unnerby to Haven to Nizhnimor. Sherkaner had been hoping for portable radios almost until the end, but such gear was still too bulky and no one was sure how it would operate under these conditions. So they each could talk to just one other team member. Still, they needed safety lines in any case, so the cable was no extra inconvenience.

Sherkaner led the way back to the lakeshore, with Unnerby behind him, and Nizhnimor and Haven pulling the sled. Away from their submarine, the darkness closed in. There were still glimmers of heat-red light, where exotherms had sprayed across the ground; the sub had burned tons of fuel in melting its way to the surface. The rest of the mission must be powered by just the exotherms they could carry and what fuels they could find beneath the snow.

More than anything else, the exotherms were the trick that made this walk in the Dark possible. Before the invention of the microscope, the "great thinkers" claimed that what separated the higher animals from the rest of life was their ability to survive as individuals through the Great Dark. Plants and simpler animals died; it was only their encysted eggs that survived. Nowadays, it was known that many single-celled animals survived freezing just fine, and without having to retreat to deepnesses. Even stranger, and this had been discovered by biologists at Kingschool while Sherkaner was an undergraduate, there were forms of Lesser Bacteria that lived in volcanoes and stayed active right through the Dark. Sherkaner had been very taken by these microscopic creatures. The professors assumed that such creatures must suspend or sporulate when a volcano went cold, but he wondered if there might be varieties that could live through freezes by making their own heat. After all, even in the Dark, there was still plenty of oxygen-and in most places there was a layer of organic ruin beneath the airsnow. If there were some catalyst for starting oxidation at super-low temperatures, maybe the little bugs could just "burn" vegetation between volcanic surges. Such bacteria would be the best adapted of all to live after Dark.