Harper must have been a difficult, solitary man. No one seemed to have missed his face or companionship, and his sudden return caused barely a ripple of interest. Word spread that somebody was again living inside his apartment, and the apartment's AI dutifully reported communications with acquaintances from the far-flung past. But the greetings were infrequent and delivered without urgency. Maintaining his privacy proved remarkably easy. For twenty busy years, Alone remained inside those small, barely furnished rooms. And the apartment never asked where its only tenant had been or why he had been detained, much less why this new Harper never needed to eat or drink or sleep. The machine's minimal intelligence had been damaged by Mr. Jan. Alone spent a month dismantling and mapping his companion's mental functions, and all that while he wondered if he was the same, his mind incomplete, mangled by clumsy, forgotten hands.

Harper had painted himself as an important explorer and an exceptionally brave thinker. Inside his pack, he had carried dated records about mysterious occurrences inside the Great Ship. But there were larger files at home, each one possessed by one broad topic and a set of tireless goals. In the man's long absence, those files had grown exponentially. Alone uncovered countless stories about ghosts and monsters and odd lost aliens. Over thousands of years, one thin rumor of a Builder being seen by the first scout team had become a ma.s.s of rumors and third-hand testimonies, plus a few more compelling lies, and several blatant fakes that had been discounted but never quite set aside.

Believe just a fraction of those accounts, and it would be difficult not to accept that the Great Ship was full of ancient, inscrutable aliens-wise souls born when the Earth was just so many uncountable atoms cooking inside a thousand scattered suns.

Each resident species had its preferred Builder.

Humanoids like to imagine ancient humanoids; cetaceans pictured enormous whales; machine intelligences demanded orderly, nonaqueous ent.i.ties. But fashions shifted easily and in confusing directions, dictating the key elements to the most recent fables. Each century seemed to have its favorite phantom, its most popular unmapped cavern, or one mysterious phenomenon that was fascinating yet never rose to a point where physical evidence could be found. But even a stubborn lack of evidence was evidence. Harper had reasoned that the Builders had to be secretive and powerful organisms, and of course no slippery wise and important creature would leave any trace of its pa.s.sing. Skin flakes and odd tools were never found in the deep caves, much less a genuine body, because if hard evidence did exist, then the quarry wouldn't be the true Builders. Would they?

One file focused on the Remora's ghost.

On Alone.

He had discovered references about himself in Harper's field recorder. But in his absence, new sightings and endless conjecture made for years of unblinking study. Alone absorbed every word, every murky image, fascinated by the mystery that he had walked through. According to most accounts, he was more real than the Whispers that haunted a mothballed s.p.a.ceport. But people like Harper generally preferred the Clackers who supposedly swam inside the Ship's fuel tanks, and the Demon-whiffs that were made of pure dark matter. Tens of thousands of years after the event, Alone watched the recording of him standing inside the empty hyperfiber tank-a swirl of cobalt light that could mean anything, or nothing-and he began to wonder if perhaps he wasn't quite real back then. Only recently, after all of the steps and missteps, had he acquired that rare and remarkable capacity to stand apart from Nothingness.

For every portion of the hull where he was seen, Remoras and other crew-members and pa.s.sengers had spotted at least ten more examples of the ghost wandering beneath the stars.

What if there was more than one Alone wandering loose?

He didn't know what to believe. After he abandoned the hull, those sightings fell to the level of occasional, and no Remora pretended to have spotted Wune's mysterious friend. In no file was there mention of Aasleen and the nightmare inside one of the Ship's engines. Which meant that the captains and crew were good at keeping secrets, and what else did they know? A related file focused on shape-shifting machines currently lurking in the dark corners and deepest wastes. Alone's cavern held a prominent but far from dominating place. Other realms seemed to be haunted by his kind. Dozens of sprawling, empty locations were named. But the only cavern to capture Alone's imagination was named Bottom- E. Again and again, he found sketchy accounts of tourists wandering down an empty pa.s.sageway, and when they glanced over their shoulder, a smear of dim light was silently racing out of view.

Bottom-E was an even larger cavern than Alone's old home. And if nothing else, it would provide the perfect next home.

But what if another ent.i.ty like him already lived there?

After two decades of study and consideration, Alone made one difficult choice. He identified the humans who had tried to contact Harper on his return. Most were small figures, many with criminal records and embarra.s.sing public files. But despite those same limitations, one man had all the qualifications to give aid to an acquaintance that he hadn't seen for ages.

With Harper's face and voice, Alone sent a polite and brief request.

Eighteen days pa.s.sed before any reply was offered. The recorded digital showed a smiling man who began with an apology. "I was off. Wandering in The Way of Old. It's an ammonia-hydroxide ocean. On a small scale, but it's still a hundred cubic kilometers of murk and life, and that's why I couldn't get back to you, Harper."

The man was named Perri.

"So you're interested in Bottom-E," the message continued. "I can't promise much in the way of help. I haven't seen more than one-tenth of one percent of the place. But there is one enormous room that's worth the long walk. Its floor is hyperfiber, and a fine grade at that. And the ceiling is kilometers overhead and inhabited by the LoYo. They're machines, not sentient as individuals but colonial in nature. A few thousand of their city-nests hang free from the rafters, and that's one of the reasons for going down there."

The grinning man continued. "The LoYo give that big room a soft, delicious glow. I've got good eyes, but even after a week in that, I couldn't see far. The immediate floor and what felt like a distant, unreachable horizon. Once, maybe twice, I saw a light in the distance. I can't say what the light was. But you know me, Harper. Don't expect ghost stories. Usually the truth is a lot more interesting than what we think we want to see...

"Anyway, what I like best about Bottom-E, and that huge room in particular...what makes the trip genuinely memorable...is that when you walk on that smooth hyperfiber, and there's nothing above you but the faint far-off glow of what could be distant galaxies...well, it's easy to believe that this is exactly how it would have felt and looked just a couple billion years ago, if you were strolling by yourself, walking across the hull of the Great Ship.

"Understand, Harper? Imagine yourself out between the galaxies, crossing the middle of nothing.

"I think that's an experience worth doing," Perri said.

Then with a big wink, he added, "By the way. I know you keep to yourself. But if you feel willing, you're more than welcome to visit my home. For a meal, let's say. For conversation, if nothing else. I don't think you ever met my wife. Well, I'll warn you. Quee Lee likes people even more than I do, if you can believe that."

Perri paused, staring at his unseen audience.

"You were gone a very long time," he mentioned. "Jan claimed you were off chasing Clackers, and that's what the official report decides too. Lost in the fuel tanks somewhere. But I didn't hear any recent news about bodies being fished out of the liquid hydrogen, which makes me wonder if our mutual friend was telling another one of his fables.

"Anyway, good to hear from you again, Harper. And welcome back to the living!"

11.

As promised, Bottom-E held one enormous room, and except for the occasional smudge of cold light on the high arching ceiling, the room was delightfully dark. Each step on the slick floor teased out memories. That lost and now beloved childhood returned to him, and Alone wasn't just content, but he was confident that the next step would bring happiness, and the one after, and the one after that.

More than twelve hundred square kilometers of hyperfiber demanded his careful study. Unlike the hull, there was an atmosphere, but the air was oxygen-starved and nearly as cold as s.p.a.ce. Like before, Alone's habit was to follow a random line until an oddity caught his attention. Then he would stop and study what another visitor had left behind-a fossilized meal or frozen bodily waste, usually-and then he would attack another random line until a new feature caught his senses, or until a wall of rough feldspar defined the limits of this illusion.

For almost two years, he walked quietly, seeing no one else.

The LoYo were tiny and weakly lit, and there was no sign that they noticed him, much less understood what he was.

Perri's mysterious glow failed to appear. But Alone soon convinced himself that he'd never hoped the story would prove real. One step was followed by the next, and then he would pause and turn and step again, defining a new line, and then without warning, there was a sliver of time when that simple cherished pattern failed him. He suddenly caught sight of a thin but genuine reddish light that his big eyes swallowed and studied, examining the glow photon by photon, instinct racing ahead of his intelligence, a.s.suring him that this new light was identical to the glow he leaked when he was examining a fossilized pile of alien feces.

On his longest, quietest legs, Alone ran.

Then the voice returned. Decades had pa.s.sed since the last time Alone felt its presence, yet it was suddenly with him, uttering the concept, "No," wrapped inside a wild, infectious panic.

His first impulse was to stop and ask, "What do you want?"

But the red glow was closer now, and Alone's voice, even rendered as a breathless whisper, might be noticed. If that other ent.i.ty heard him, it could become afraid, vanishing by some secret means. The moment was too important to accept that risk. The end of a long solitude might be here, if only Alone was brave enough to press on. That's what he had decided long ago, imagining this unlikely moment. He would accept almost any danger to make contact with another like him. But only now, caught up in the excitement, did Alone realize how much this mattered to him. He was excited, yes. Thrilled and spellbound. Every flavor of bravery made him crazy, and he refused to answer the voice or even pay attention when it came closer and grew even louder, warning him, "Do not." Telling him, "No. They want, but they will not understand. Do not."

The light was still visible, but it had grown weaker.

The intervening distance had grown.

The other Alone must have noticed something wrong. A footfall, a murmur. Perhaps his brother heard the voice too, and the wild, unapologetic fear had taken possession of him. Whatever the reason, the light was beginning to fade away, losing him by diving inside a little tunnel, abandoning this room and possibly Bottom-E because of one irresistible terror.

Alone had to stop his brother.

But how?

He quit running.

The voice that had never identified itself-the conscience that perhaps was too ancient, too maimed and run down, to even lend itself a name-now said to him, "Go away. This is the wrong course. Go!"

Alone would not listen.

Standing on that barren plain, he made himself grow tiny and exceptionally bright, washing away the darkness. In an instant, the enormous chamber was filled with a sharp white light that reached the walls and rose to the ceiling before vanishing in the next instant.

Then he was dark again, drained but not quite exhausted.

With the last of his reserves, Alone spun a fresh mouth, and in a language that he had never heard before-never suspected that he was carrying inside himself-he screamed into the newly minted darkness, "I am here!"

Suddenly a dozen machines emerged from their hiding places, plunging from the ceiling or racing from blinds inside the towering rock walls.

Alone tried to vanish.

But the machines were converging on him.

Then he grew large again, managing legs. But the power expended by his desperate flash and careless shout was too much, and too many seconds were needed before he would be able to offer the many kind of chase. After thousands of years, the door of a trap was closing over him, and in the end there wouldn't even be the pleasure of a hard chase fought to the dramatic end.

12.

Since their last meeting, the two organisms had walked separate lines-tightrope existences inspired by chance and ambition, deep purpose and the freedom of no clear purpose. An observer on a high perch, watching their respective lives, might have reasonably concluded that the two souls would never meet again. There was no cause for the lines to cross. The odd machine was quiet and modest, successfully avoiding discovery in the emptiest reaches of the Ship, while the engineer was busy maintaining the giant engines, and later, she was responsible for a slow-blooming career as a new captain. The remote observer would have been at a loss to contrive any situation that would place them together, much less in this unlikely terrain. Embarra.s.sed, Aasleen confessed that she had had no good idea where Alone might have been and not been over these last tens of thousands of years. For decades, for entire centuries, she didn't waste time pondering the device that she once cornered and then let get away. Not that she was at peace with her failure. She was proud of her competence and didn't appreciate evidence to the contrary. Somewhere onboard the Great Ship was a barely contained speck of highly compressed matter, and should that speck ever break containment, then the next several seconds would become violent and famous, and for some souls, exceptionally sad.

This was a problem that gnawed, when Aasleen allowed it to. But as an engineer, she handed her official worries to the Submaster Miocene, and as a novice captain, she had never once been approached with any duty that had even the most glancing relationship to that old problem.

She told her story now, a.s.suming that her prisoner would both understand what he heard and feel interested in this curious, quirky business.

Then several centuries ago, Aasleen and another captain met by chance and fell into friendly conversation. It was that other captain who mentioned a newly discovered machine-building species. Washen had a talent for aliens, Aasleen explained. Better than most humans, her colleague could decipher the att.i.tudes and instincts of organisms that made no sense to a pragmatic, by-the-number soul like her. But the aliens, dubbed the Bakers, had been superior engineers. That's why Washen mentioned them in the first place. She explained their rare genius for building inventive and persistent devices, and millions of years after their rise and fall and subsequent extinction, their machines were still scattered across the galaxy.

"Bakers is our name for them," Aasleen cautioned. "It shouldn't mean anything to you."

Alone was floating above the cavern floor, encased in a sequence of cages, plasmas and overlapping magnetic fields creating a prison that was nearly invisible and seemingly unbreakable. Drifting in the middle of the smallest cage, he was in a vacuum, nothing but his own body to absorb into an engine that everybody else seemed to fear. With a flickering radio voice, he agreed. "I don't know the Bakers."

"How about this?" Aasleen asked.

Another sound, intense and brief, washed across him. He listened carefully, and then he politely asked to hear it again. "I don't know the name," he confessed. "But the words make sense to me."

"I'm not surprised," Aasleen allowed.

Alone waited.

"We know what you are," she promised.

His response, honest and tinged with emotion, was to tell his captor, "I already know what I am. My history barely matters."

"All right," Aasleen allowed. "Do I stop talking? Should I keep my explanations to myself?"

He considered the possibility. But machines and teams of engineers were working hard, obviously preparing to do some large job. As long as the woman in the mirrored uniform was speaking, nothing evil would be done to him. So finally, with no doubt in the voice, he said, "Tell me about these Bakers."

"They built you."

"Perhaps so," he allowed.

"Seven hundred million years ago," Aasleen added. Then a bright smile broke open, and she added, "Which means that you are the second oldest machine that I have ever known."

The Great Ship being the oldest.

Quietly, with a voice not quite accustomed to lecturing, she explained, "The Bakers were never natural travelers. We don't know a lot about them, and most of our facts come through tertiary sources. But as far as we can determine, that species didn't send even one emissary out into the galaxy. Instead of traveling, they built wondrous durable drones and littered an entire arm of the galaxy with them. Their machines were complicated and adaptable, and they were purposefully limited in what they knew about themselves. You see, the Bakers didn't want to surrender anything about themselves, certainly not to strangers. They were isolated and happy to be that way. But they were also curious, in a fashion, and they could imagine dangerous neighbors wanting to do them harm. That's why they built what looks to me like an elaborate empty bottle-a bottle designed to suck up ideas and emotions and history and intellectual talents from whatever species happens to come along. And when necessary, those machines could acquire the shape and voice of the locals too."

Nothing about the story could be refuted. Alone accepted what he heard, but he refused to accept that any of it mattered.

Aasleen continued, explaining, "The Bakers lasted for ten or twelve million years, and then their world's ecosystem collapsed. They lived at the far end of our galaxy, as humans calculate these measures. The only reason we've learned anything about them is that one of our newest resident species have collected quite a few of these old bottles. In partial payment for their ongoing voyage, they've shared everything they know about the Bakers. It's not the kind of knowledge that I chase down for myself. But Washen knew that I'd be interested in dead engineers. And she mentioned just enough that I recognized what was being described, and I interrupted to tell her that I knew where another bottle was, and this one was still working.

"'Where is it?' she asked.

"I told her, 'Wandering inside the Great Ship, he is, and he answers to the very appropriate name of Alone.'"

The captain paused, smiling without appearing happy.

Alone watched the workers. An elaborate needle was being erected on the cavern floor, aiming straight up at him.

"We approached Miocene with our news," Aasleen continued. "I know Washen was disappointed. But I was given the job of finding you again, and if possible, corralling you. Washen helped me profile your nature. Your powers. I decided to lure you in with the promise of another machine like you, and that's why I turned Bottom-E into a halfway famous abode for a glowing shape-shifting soul. If something went ugly-wrong down here, then at least the damage could be contained."

"What about the LoYo?" Alone asked.

"They've been moved to other quarters. The lights above are hiding sensors, and I designed them myself, and they didn't help at all. Until that light show, we couldn't be certain that you were anywhere near this place."

The needle was quickly growing longer, reaching for the cage's outermost wall.

"What will you do now?" Alone asked.

"Strip away your engine, first. And then we'll secure it and you." Aasleen tried to describe the process, offering several incomprehensible terms to bolster her expertise. But she seemed uneasy when she said, "Then we'll isolate your neural net and see what it is and how it works."

"You are talking about my mind," Alone complained.

"A mind that lives beside a powerful, unexploded bomb," the captain added.

"The Bakers didn't design you to survive for this long. My best guess is that you pushed yourself outside the Milky Way, and in that emptiness, nothing went wrong. You drifted. You waited. I suppose you slept, in a fashion. And then you happened upon the Great Ship, before or after we arrived. You could have been here long before us, but of course the Bakers are lost, and you weren't what I would consider sentient."

"But I am now," he said, his voice small and furious.

Aasleen paused.

Without apparent effort, the needle began to pa.s.s through the wall of the first impenetrable cage.

"You are going to kill me," he insisted.

The human was not entirely happy with these events. It showed in her posture, her face. But she was under orders, and she was confident enough in her skills to say, "I don't think anything bad will happen. A great deal of research and preparation has been done, and we have an excellent team working on you. Afterwards, I think you'll prefer having all of your memories pulled loose and set inside safer surroundings."

With a sudden thrust, the needle pierced the other cages, and before it stopped rising, its bright plasmatic tip was touching his center.

Damage was being done.

Quietly but fiercely, he begged Aasleen, "Stop."

One of the nearby machines began to wail, the tone ominous and quickening. Aasleen looked at the data for a moment, and then too late, she lifted one of her hands, shouting, "Stop it now. We've got the alignment wrong-!"

Then the captain and every engineer vanished.