“These are skills,” says the supervisor. “This is a job.”

Seymour nods. On the screen in front of him, the Earth spins. The view sinks through digital clouds over a swath of South America—Brazil maybe—and touches down on a rural highway as straight as a ruler. Red dirt runs down both sides; what might be sugarcane grows beyond that. He nudges the trackball forward: the flag ahead gradually enlarges as he draws closer.

Beneath it, a little blue sedan has struck a cow head-on, and the car is crumpled, and there is blood on the road, and a man in jeans is standing beside the cow with his hands behind his head, either watching it die or trying to figure out if it is going to die.

Seymour confirms the flag, circles the image, and in an instant the cow, car, and man are concealed with a section of computer-generated roadway. Before he has time to process any of it, the software whisks him to the next flag.

A faceless little boy in front of a roadside churrascaria shows the camera his middle finger. Someone has painted a penis on the sign of a little Honda dealership. He checks forty flags around Sorriso, Brazil; the computer launches him back into the troposphere, the planet spins, and he drops into northern Michigan.

Sometimes he has to poke around a bit to understand why a flag has been placed. A woman who might be a prostitute leans into a car window. Beneath a church marquee that says GOD LISTENS, someone has spray-painted TO SLAYER. Sometimes the software misinterprets a pattern of ivy for something obscene, or flags a kid walking to school for reasons Seymour cannot guess. He rejects or verifies the flag, draws an outline around the offending image with his cursor, and it’s gone, hidden behind a high-resolution bush or erased by a smear of counterfeit sidewalk.

The movement chime sounds; the other two men trundle off to lunch; Seymour stays put. By roll call, he has not moved for nine hours; the supervisor is gone; an old man sweeps beneath the teaching terminals; the windows are dark.

* * *

They pay him sixty-one cents an hour, which is eight more cents than the guys make in the furniture shop. He’s good at it. Pixel by pixel, boulevard by boulevard, city by city, he helps Ilium sanitize the planet. He effaces military sites, homeless encampments, queues outside medical clinics, labor strikes, demonstrators and dissidents, picketers and pickpockets. Sometimes he comes upon scenes that engulf him with emotion: a mother and son, bundled in parkas, holding hands beside an ambulance in Lithuania. A woman in a surgical mask kneeling on a Tokyo expressway in the middle of traffic. In Houston several hundred protesters hold banners in front of an oil refinery; he half expects to recognize Janet among them, twenty new frog patches sewn on her jean jacket. But all the faces are blurred, and he confirms the flag, and the software replaces the protesters with thirty digital sweetgum saplings.

Seymour Stuhlman’s stamina, the Ilium supervisors report, is remarkable. Most days he triples his quotas. By the time he is twenty-four, he is a legend in the Ilium Earth offices, the most efficient cleaner in the entire prison program. They send him an upgraded terminal, give him his own corner of the computer room, and raise his pay to seventy cents an hour. For a while, he manages to convince himself that he’s doing something good, removing toxicity and ugliness from the world, rinsing the earth of human iniquity and replacing it with vegetation.

But as the months tick past, especially after dark, in the isolation of his cell, he sees the old man in the dark of the library, wobbling in his penguin tie, holding the green backpack to his chest, and doubts worm their way in.

He’s twenty-six when Ilium develops its first treadmill prototype. Now rather than sit at a terminal and twitch through spaces with a scroll wheel, he’s walking through them on his own two feet, helping the AI cleanse the map of the ugly and the inconvenient. He averages fifteen miles a day.

* * *

One afternoon when Seymour is twenty-seven, he puts on his wireless headset, saturated with the smell of his own sweat, mounts the treadmill, hangs over the Earth, and a dark blue lake in the rough shape of a G comes flying toward him.

Lakeport.

The town has metastasized over the past decade, condos grown like carbuncles around the southern shore of the lake, housing developments unfurling beyond that. The software drops him in front of a liquor store where someone has shattered a front window; he fixes it. Then to a pickup truck driving along Wilson Road, its bed jammed with teenagers. A banner streaming behind them reads: You’ll die of old age, we’ll die of climate change. He traces an oval around them, and the truck evaporates.

The icon he’s supposed to touch to send him to his next flag flashes; instead Seymour begins walking home. A quarter mile down Cross Road, the aspens are turning gold. An automated voice crackles in his headset, Moderator 45, you are traveling in the wrong direction. Please head to your next flag.

The Eden’s Gate sign is still there on the side of Arcady Lane. The double-wide is gone, the acre of weeds replaced by three townhomes with overwatered lawns, so seamlessly integrated into the other homes on Arcady Lane that it looks as though software has placed them there instead of carpenters.

Moderator 45, you are off course. In sixty seconds you will be sent to your next flag.

He breaks into a run, heading east down Spring Street, the treadmill bouncing beneath his feet. Downtown, at the corner of Lake and Park, the library is gone. There’s a new hotel in its place, three stories with what looks like a rooftop bar. Two teenaged valets in bow ties stand out front.

Junipers gone, book drop box gone, front steps gone, library gone. Into his mind flickers a vision of the old man, Zeno Ninis, sitting at a little table in Fiction, hunched behind stacks of books and legal pads, his eyes damp and cloudy, blinking as though watching words flow invisibly in rivers around him.

Moderator 45, you have five seconds…

Seymour stands on the corner, breathing hard, feeling as though he could live a thousand more years and never make sense of the world.

Redirecting you now.

He is yanked straight up into the air, Lakeport shrinking to a dot, the mountains swiveling away, southern Canada unfurling far below, but something has gone wrong inside him; everything is spinning; Seymour falls off the treadmill and breaks his wrist.

May 31, 2030

Dear Marian,

I know that I will never understand all the consequences of what I have done or apprehend all the pain I caused. I think of the things you did for me when I was young and you should not have to do any more. But I was wondering. During the trial I learned that Mr. Ninis worked on translations and that he was working on a play with the children before he died. Do you know what became of his papers?

Yours,

Seymour

Nine weeks later, he is called to the prison library. An officer wheels in a dolly stacked with three cardboard boxes marked with his name and red Scanned stickers.

“What’s all this?”

“They just told me to bring it here.”

Inside the first carton is a letter.

July 22, 2030

Dear Seymour,

I was happy to hear from you. Here is everything I could gather from the trial, from Mr. Ninis’s house, and that we recovered at the library. The police might have more, I’m not sure. Nobody ever did anything with all this, so I’m trusting you with it. Access is part of the librarian’s creed, after all.