Thumps resounded from beyond my door, but I knew it was just The Arrow’s ailing bones. Rodrigo wasn’t coming back.

I tipped my chair back and stared at my lichen-spotted ceiling. Around me, The Arrow sang its swan song — rattling vents, pops from speakers, the hiss of leaking steam. I’ve lived throughout this jungle all my life, on fifteen different decks, and I know the distinct rhythms of its failure. The thumps in the hall were from the cooling and contraction of some hidden metal element — probably — and had started ten months prior. They were nothing like the tmp-tmp-tmp of human footsteps.

The clock on my monitor read 10:58. I couldn’t blame Rodrigo; not really. The reason he had given up was right there on my screen:

ERNAL PRESSURE IDEALIZED RANGE 0 MPA 235 MPA (FIG. 32C-32CA), OPERATIONAL EFFECTIVENESS SUBJECT TO LOGARITHMIC DECREASE (FIG. 32CB INSET) REFER SECTION 6.6.2 SUBHEADING ‘MICROTENSILE GAUGES’. IF EXCEEDING 275 MPA EFFECTIVE D

I drummed my fingers on the desk, leaving prints on the moist surface. On the upper left corner of my monitor, the longstanding patch of mutant fungus had gotten larger. The farmers aboard The Arrow call such anomalies egg-mould, but I think the fungal colonies look like eyes: a ring of white around a ring of green around a pit of black, in raised globules that first appear as tiny speckles upon any damp surface, until they each expand out and out and out, and The Arrow’s knife-toothed kids strip naked and fuck in front of whole walls of them for an exhibitionist thrill. Rodrigo told me. “We got the idea from Boro,” he said. “Boro knows everything.”

I thought about sitting in my rooms and sulking the whole day, but that wasn’t a real solution. Not in the long run, anyway. Rodrigo was forty years younger than me and The Arrow’s last hope, and if I let him slip away without a fight, it wasn’t just my pride that would be crippled.

The Arrow is big — really big — but there are only so many places aboard that people will live. Some corridors have no functioning lights; some sections make people choke and die; some places permanently sealed themselves off to contain some long-ago disaster. In some areas there are moulds and insects and lichens, or birds and lizards, even, things that escaped the designated habitat areas generations ago and have established their own radical ecologies upon The Arrow’s dribbles of leaking water. On Deck 18, there is even a colony of feral, rail-thin cats. They’re not afraid of people, and they bite.

It was all to my advantage. Other people didn’t want to hop over broken deck plates or crawl under collapsed doorways: So as long as I chose to live deep inside the jungle, I was never bothered. Only Rodrigo knew what route to take to find me, and he was the only one I wanted to be found by.

The hike out from the jungle took about half an hour. From there, finding Rodrigo was easy. I spotted him at the gardens, on the starboard side of the town commons, the open, cavernous space at the heart of The Arrow. Other people gave me an even wider berth than usual as I crossed the open floor toward him. One woman spit at my feet. Another grabbed her arm and hissed, “Don’t even look. You’ll encourage him.”

Rodrigo sat with a troop of kids below a raised bed of Swiss chard. Above them, sitting on the low wall of the garden plot, Dr. Chester Hillsboro regarded the troop with eyelids lowered in benign contemplation. His left arm was a tableau: half-raised, wrist limp, delicately pinching a sprig of plucked khat. Dr. Hillsboro took a turtle-slow chomp of it. Chewed. Cupped the narcotic khat leaf within his cheek. “The nonlinear nature of the universe confers a fundamentally incompatible framework upon which our two-dimensional experiential cognizance cannot attach a referential anchor-point from which to construct an operational understanding of the conceptual underpinnings.”

I pushed through the troop of kids. They gripped bunches of khat, too, and harder stuff, or nothing, or each other. Some snickered and ignored Dr. Hillsboro, and some loitered at the fringes, teeth gleaming like broken glass.

“Rodrigo!”

Kids turned those gleaming teeth toward me. A wince flashed over Rodrigo’s face, but he quickly snuffed it in cool indifference. “What?”

“Get over here.”

“Why?”

“You’re late for work.”

More kids turned. “Work,” said Rodrigo, loudly. “I don’t believe in that anymore.”

Dr. Hillsboro paused. The bed of chard he perched upon abutted the town commons starboard wall, where a line of those false fungal eyes, like a pearl necklace of the damned, stretched up to the ceiling along a dribbled line of well-established moisture. “Dr. Jin Kim. Come join us, in blessed contemplation of the mysteries.”

I grabbed Rodrigo’s arm and yanked him to his feet. The other kids laughed.

“Believe in The Arrow slowly rotting in space, off course by God knows how much, and nobody knowing how to fix her. You think it’ll be like this forever? That the human race has nothing to do but wait and fuck-all until, if ever, The Arrow finally comes within range of Haven’s orbit, and the homing and auto-landing sequences begin?”

Rodrigo looked around, forcing a laugh. Maybe generations-old, shit-written tech documentation hadn’t been why he’d quit. Maybe he’d simply quit because he was thirteen and he wasn’t strong enough. “Come on. We’ll get to Haven real soon anyway. In like a year.”

“And you have reason to believe this because? The Arrow’s deep space navigational system went down all the way back when my grandfather was a boy, and nobody—”

“Your grandfather,” one kid snickered.

“Whatever, hey,” said another kid. She rolled an empty plastic cup between her palms. “They corrected the world’s course or something, back when that thing happened. So it doesn’t matter.”

Another kid punched her in the arm. “You aren’t even supposed to talk to him.”

“They did correct it,” I said to the first girl. She rubbed her arm and wouldn’t look at me, now, but I kept going. “The issue is, because of the damage to the system, we can’t tell to what degree that long-ago course correction was. Which is why we might never get to where our ancestors hoped we would go — not until we fix The Arrow, learn for certain where we are and how we’re moving, and make more course corrections. And—”

“BOO,” bellowed an older boy, big enough to have scruff on his chin. Any day now, he’d abandon Dr. Hillsboro’s self-indulgent ravings and drift over to one of the adult social troops, drawn in by the more mature goose-chases of grown-ups. “Peddle your religion somewhere else. This is Boro’s turf.”

“It’s not religion! These things happened, Goddammit!”

“Encoding key cultural memes and information in subconsciously universal narrative structures bypasses the inherent fallacy of the supposition of the nature of truth,” said Dr. Hillsboro. “Myth and folklore is the only way forward now, Jin. For history and physics both.”

“This is bullshit,” I shouted. “You all know what a planet is. You all know what a colony ship is.”

“Sure,” said a girl who leaned against the wall. “Boro’s told us. We’re all little specks of life, floating in an infinite void, and sometimes we come together, and sometimes we” — she plucked orbs of fungus off the wall, a crow snatching out the eyes of the dead — “come apart.”

“No,” I said, despairing. “A planet is a gigantic ball of matter, trillions of times larger than a ship.”

Rodrigo wriggled out of my grasp. “We’re done. Okay? I’m not reading any more stupid stuff that doesn’t make sense so I can try to change a world we weren’t meant to fully understand anyway.”

“We built this world!”

“Through the intersectionality of agent and object, force and target, action and reaction,” said Dr. Hillsboro, “essential dichotomies redefine experiential vectors and create a reiterative resonance between creator and that which is created.”

“Not like that,” I said, but everyone had stopped listening to me. “Not like that.”

Rodrigo grumbled and sat back down. Other kids dismissed me with bored sighs. Overhead, the huge lights that fed the gardens buzzed too loudly, stars nearing the ends of their stable lives. A fungal eye at my feet stared up at them, unblinking, going blind.

I was too angry to speak further. I left.

A kid caught up to me on the way to the exit. “Hey,” she said. She looked like all the others: ratty hair, torn rags for clothes, bare feet calloused from a life misspent, sprinting over diamond-patterned deck. “Fuck Rodrigo. He just thinks he’s being cool. He used to tell me all about his work with you. The Manuals of Tech, right? That’s what the books are called? And you can … you can change the world with them.” She pulled a lock of hair around an inquisitive finger. “You can keep the world from collapsing.”

“Yes.” I watched her face. “Yes we can.”

She nodded. Her eyes were far away, but her mouth was serious. “That sounds cool. Can you show me? Since Rodrigo doesn’t want to be your apprentice anymore?”

Hope flared within me. I nearly screamed it. “Yes.”

Her name was Sabbi and she was fourteen. Too old to start most apprenticeships, especially one under a Functional Historian, but I didn’t know if Rodrigo would ever change his mind, and I had to assume it was Sabbi or nothing.

I took her through the jungle to my rooms. She kept glancing back the whole way, as if afraid of being followed, or maybe just judged. At that thought, I felt a little sorry for her. The work itself was hard enough, but the flak she’d catch from the other kids for spending time with me would make it a lot worse.

“The first thing I’ll do is unpack what we mean by Functional History, and that in itself will take some time, because the term is a relatively new invention that only has real meaning in the context of The Arrow.”

“Uh-huh.”

We climbed over a discarded couch, wedged lengthwise in the hallway. “Then I’ll give you a brief run-down of the areas of specialization.”

“Okay.”

“From which I’ll explain what the lost disciplines are, why they’re important, and how I’m trying to revive them, which is my lifelong area of active research. If we can get The Arrow’s DSN system back online, we’ll know where humankind is going and we’ll have the tools to change it.”

Sabbi turned a mouldering throw pillow over with one foot, revealing a veneer of gunk on its reverse side. “Yeah.”

“Any questions so far?”

She looked around. “Are you sure we have to get to your house this way?”

Once in my rooms, I gave her some introductory lectures. Like Rodrigo, she had zero background in science. When I was a kid, The Arrow had a formal school, and not what happens in the gardens. We had a long way to go.

She fidgeted the whole time.

At 08:13 the next morning, I heard a new noise. Thumps and slaps, hisses and squeals. I didn’t know the sound at all, and, fearing the worst, I opened my doors and stepped into the hall.

A wall of broken-glass teeth gleamed back.

“What the—”

They lunged forward like the Deck 18 cats do, yowling and unafraid. Countless hands grabbed and punched, and while they’re just kids, I’m just one man. The deck vanished beneath me below a net of fingers and fists.

“Sabbi!” I shouted. Hot fear surged through me. They had followed her yesterday, and had thereby learned where to find me, at long last. How long had they been waiting, to descend upon me like this? Or—

—Or maybe Sabbi had set me up.

But either way — did it matter?

I tried to see past jabbing knuckles and slamming knees. Sabbi wasn’t there. “Sabbi! Rodrigo!”

They carried me through dark corridors, below torn and sparking conduits, past walls speckled with eyes, a million tiny colonies in their isolated bubbles. The kids swore and sang, laughed and spit. They yanked my hair and pinched my ears. Someone bit my hand until it bled.

I knew the jungle better than anyone, but even if I hadn’t, I could’ve guessed where we were going. We passed a sign that said MAINTENANCE PORTAL 96-2-4H and I knew that

FROM WHCH TO ACCESS EXTERIOR REPAIR NECESSITIES THE MAINTENANCE PORTALS BEING LOCATED 108.3 M APART 5 32 54.5 AND 88 DEGREES LONGITUDINAL FROM DORSO AND VERTIC

Mouths and broken pipes hissed. The walls here were wet, streaked with tears and trails of wet and wet, and cyclopean eyes dropped to the deck under their own pendulous weight and the slaps of calloused feet. Hands pretended to drop me. I kicked at humid air, screaming for children to save me from children, and ragged nails raked my face.

We stopped at a wall. Dr. Hillsboro stood waiting, arm outstretched, limp-wristed hand hovering near a button, as if merely gesturing at its existence. Click. A pair of doors pulled apart in triumph.

They threw me into the airlock. I hit the floor on my shoulder, badly and wrong, and I cried out.

“Exigencies of identity rubrics and social cohesion in a post-planetary reality necessitate the concretized expulsion, in a symbolically significant way, of the embodiment of the disruptor to which cultural anxieties and points of friction are inevitably attached,” said Dr. Hillsboro. “So please understand. It’s nothing personal.”

They closed the airlock’s inner doors. An alarm sounded, a surprisingly beautiful thing, a song new to me in The Arrow’s mortal symphony.

The alarm is fading, now, as that outer pair of doors on the airlock’s other wall cracks open. It’s small in here. I still don’t see Sabbi, but finally here’s Rodrigo, one arm entangled in an equipment net.

The walls here are so clean. And Rodrigo’s emptied eye sockets, such black pits of nothing.