Bunny lays a 1.69-ounce package of plain M&M’s on the table. Beside that she sets an orange bottle with a white cap. “The doctor said they won’t make you dumb. They’ll just make things easier. Calmer.”

Seymour grinds the heels of his hands into his eyes. The ghost of Trustyfriend hops to the sliding door. His tail feathers are gone; one wing is missing; his left eye is damaged. His beak is a dash of yellow in a radar dish of smoke-colored feathers. Into Seymour’s head he says, I thought we were doing this together. I thought we were a team.

“One in the morning,” Bunny says, “and one at night. Sometimes, kid, we all need a little help shoveling the shit.”

Konstance

She is walking a street in Lagos, Nigeria, passing through a plaza near the waterfront, gleaming white hotels rising around her on all sides—a fountain caught mid-spray, forty coconut palms growing from black-and-white checkered planters—when she stops. She peers up, a faint prickling at the base of her neck: something not quite right.

In Farm 4 Father has a single coconut in a cold-storage drawer. All seeds, he said, are voyagers, but none more intrepid than the coconut. Dropped onto beaches where high tides can pick them up and carry them to sea, coconuts, he said, regularly crossed oceans, the embryo of a new tree safe inside its big fibrous husk, twelve months of fertilizer provisioned on board. He handed it to her, vapor rising from its shell, and showed her the three germination pores on the bottom: two eyes and a mouth, he said, the face of a little sailor whistling its way around the world.

To her left a sign says, Welcome to the New Intercontinental. She steps into the shade of the palms and continues squinting up when the trees ribbon away, her Vizer retracts from her eyes, and Father is there.

She feels the familiar lurch of motion sickness as she steps off her Perambulator. It’s NoLight already. Mother sits on the edge of her bunk working sanitizing powder into the folds of her palms.

“I’m sorry,” Konstance says, “if I was in there too long.”

Father takes her hand. His white eyebrows bunch. “No, no, nothing like that.” The only illumination comes from the lavatory light. In the shadows behind him she can see that Mother’s usually orderly stack of worksuits and patches has been upended, and her button bag is spilled everywhere—buttons under her bunk, under the sewing stool, in the curtain track around the commode.

When Konstance looks back up at her father, some part of her understands before he speaks what he will say, and she feels so acutely that they have left their planet and star behind, that they move at impossible speeds through a cold and silent void, that there is no turning around.

“Zeke Lee,” he says, “is dead.”

* * *

One day after Ezekiel’s death, Dr. Pori dies, and Zeke’s mother has reportedly lost consciousness. Twenty-one others—one quarter of the people on board—are experiencing symptoms. Dr. Cha spends her every hour tending to crew members; Engineer Goldberg works through NoLight in the Biology Lab trying to solve it.

How does a plague start inside a sealed disc that has had no contact with any other living thing for almost six and a half decades? Is it spreading via touch or spittle or food? Via the air? The water? Was deep-space radiation penetrating the shielding and damaging the nuclei of their cells, or was it something asleep in someone’s genes, all these years, suddenly waking up? And why can’t Sybil, who knows all things, solve it?

Though he has hardly used his Perambulator in Konstance’s memory, her father now spends nearly every waking hour on it, Vizer locked over his eyes, studying documents at a Library table. Mother maps the minutes before quarantine. Did she pass Mrs. Lee in a corridor, did some microscopic fleck of Ezekiel’s vomit land on her suit, could some of it have splashed into their mouths?

A week ago, it all seemed so secure. So settled. Everyone whispering down the corridors in their patched-up worksuits and socks. You can be one, or you can be one hundred and two… Fresh lettuce on Tuesdays, Farm 3 beans on Wednesdays, haircuts on Fridays, dentist in Compartment 6, seamstress in Compartment 17, precalc with Dr. Pori three mornings a week, the warm eye of Sybil keeping watch over them all. Yet, even then, in the deepest vaults of her subconscious, didn’t Konstance sense the terrible precariousness of it all? The frozen immensity tugging, tugging, tugging at the outer walls?

She touches her Vizer and climbs the ladder to the second tier of the Library. Jessi Ko looks up from a book in which a thousand pale deer with oversized nostrils lie dead in snow.

“I’m reading about the saiga antelope. They had this bacteria in them that caused massive die-offs.”

Omicron lies on his back, gazing up.

“Where’s Ramón?” Konstance asks.

Below them images from long-ago pandemics flicker above grown-ups at tables. Soldiers in beds, doctors in hazmat suits. Unbidden into her head comes an image of Zeke’s body being sent out the airlock, then Dr. Pori’s a few hundred thousand kilometers later: a trail of corpses left through the void like breadcrumbs from some ghastly fairy tale.

“Says here that two hundred thousand of them died in twelve hours,” Jessi says, “and no one ever figured out why.” Far down the atrium, at the limit of her eyesight, Konstance sees her father at a table by himself, sheets of technical drawings sailing around him.

“I heard,” says Omicron, staring up through the barrel vault, “that Quarantine Three lasts a year.”

“I heard,” whispers Jessi, “that Quarantine Four lasts forever.”

* * *

Library hours are extended; Mother and Father hardly leave their Perambulators. More unusual still, inside Compartment 17, Father has taken down the bioplastic privacy curtain that enclosed the commode, snipped it into pieces, and is using Mother’s sewing machine to make something with it—she hasn’t dared to ask what. Sealed in Compartment 17, beneath the miasma of nutritional paste burping out of the food printer, Konstance can almost smell the collective fear as it moves through the ship: insidious, mephitic, seeping through walls.

Later, inside the Atlas, on the outskirts of Mumbai, she travels a jogging trail wound around the bases of huge, cream-colored towers, forty or fifty stories high. She slips past women in saris, women in jogging suits, men in shorts, everyone motionless. To her right, a wall of green mangroves runs alongside the trail for a half mile, something troubling her as she moves through the frozen joggers, some disquieting wrinkle in the texture of the software: in the people or the trees or the atmosphere. She picks up her pace, uneasy, passing through figures as though through ghosts: with every stride she can feel the fear pervading the Argos, about to lay its hand on the back of her neck.

By the time she climbs out of the Atlas, it’s dark. Little sconces glow at the base of the Library columns and moonlit clouds scud over the barrel vault.

A few documents shuttle to and fro; a few figures hunch over tables. Mrs. Flowers’s little white dog comes trotting to her and sits with its tail swishing back and forth, but Mrs. Flowers is nowhere to be seen.

“Sybil, what time is it?”

Four ten NoLight, Konstance.

She switches off her Vizer and steps off the Perambulator. Father is at Mother’s sewing machine again, glasses low on his nose, working by the light of Mother’s lamp. The hood of his containment suit sits in his lap like the severed head of some enormous insect. She worries that he will chide her for staying up too late again, but he is mumbling to himself, brooding on something, and she realizes that she would like to be chided for staying up too late.