The rain in Los Angeles does not clean anything. It makes the grime slicker. It makes the neon signs bleed color onto the pavement. It makes the city look like a photograph that has been left out in the rain — everything still there, but blurred, the edges running together, the meaning dissolving.

Jack Callahan was repairing a radio in his garage beneath a noodle shop on Temple Street when the woman came in.

The garage was small. It smelled like solder and old cigarettes. Jack had been running it for three years — ever since he stopped working on the projects he was never supposed to talk about and started repairing radios for people who did not need radios but bought them anyway because they wanted to hear voices from far away.

The woman was beautiful in the way that beautiful women in Los Angeles always are — carefully, artfully, with a degree that cost more than Jack's annual income. She wore a black coat that was wet from the rain and a hat that did not match and shoes that had never walked on anything rougher than a carpet.

She handed Jack an envelope of cash and a set of blueprints.

"Can you look at these?" she said.

Jack looked at the envelope. It was thick. He did not open it. He looked at the blueprints. They were rolled and tied with a piece of string. He untied the string and unrolled them on the workbench.

They showed a machine. A machine that looked like an engine but was not an engine. It was something else — something that Jack recognized from his days at the laboratory, from the projects he was never supposed to talk about.

It was a device designed to push a planet out of its orbit.

He stared at the blueprints. The woman stared at him. The rain fell outside. The radio on the workbench crackled with a voice from somewhere far away.

"Where did you get these?" Jack said.

"The dead man's study," the woman said. "His name was — "

"You don't need to tell me his name."

"I know. But you should know that he died three weeks ago. In a car accident on the PCH. Or so the police said."

Jack rolled up the blueprints. He tied them with the piece of string. He put them in his desk drawer.

"I'm not interested," he said.

The woman smiled. It was not a nice smile. "You're already interested. You looked at the blueprints. You recognized them. You know what they are."

"I know a lot of things. That doesn't mean I'm interested."

She left the envelope on the workbench. Jack counted the money when she was gone. It was more than he had made in six months. He put it in a drawer beside the blueprints.

He did not think about them for three days.

On the fourth day, he took the blueprints home. He spread them on his kitchen table and studied them until two in the morning. They were beautiful — in the way that only things designed by people who understand the universe can be beautiful. Every line was precise. Every calculation was elegant. The machine was not theoretical. It was real. It had been built.

And it was not in New Mexico. The blueprints contained coordinates. Jack plotted them on a map. They pointed to a location in the California desert, approximately forty miles north of Palm Springs.

He drove out to them one night. He parked his car on a ridge and looked down into a valley. There was a facility down there. It was buried inside a mountain — or rather, it was built into the side of a mountain, with a massive entrance that looked like the mouth of a cave but was actually a steel door three stories tall.

Jack drove closer. He saw people. They were walking in and out of the facility. They were wearing lab coats. They were carrying equipment. The facility was active.

He saw the engine.

It was visible through the entrance — a massive structure of steel and glass that looked like nothing human ever built. It was cylindrical, approximately two hundred feet tall, and it was rotating slowly, very slowly, in a way that made Jack's stomach turn just to look at it.

He turned to leave and saw a man watching him from a window in the facility. The man did not look surprised.

Jack drove home. He did not sleep.

He was taken to a room the next day. Not kidnapped — taken. A man in a suit had found him. Not at his garage. At a diner on Sunset where Jack went every morning for coffee. The man had said: "Dr. Callahan, we need to talk." And Jack had gone with him because he was tired and the rain was falling and he did not have the energy to refuse.

The room was small and windowless. The man in the suit sat across from Jack and told him everything.

The government knew about the Sisyphus Engine. They had known for years. It had been built in secret, in a facility buried inside a California mountain, by a team of engineers and physicists who had been recruited from NASA and the Jet Propulsion Laboratory and a dozen other places that Jack had worked or visited or heard about.

The engine was not theoretical. It was operational. It had been operational for three years. No one outside the project knew. Jack knew because he had worked on an earlier version — a prototype that had been abandoned when it became clear that the full-scale engine would be too dangerous to operate with the technology available at the time.

"The engine is designed to push a planet out of its orbit," the man in the suit said. "The planet is not important. The principle is. If we can push a planet, we can push anything. Asteroids. Comets. Things that threaten the Earth."

Jack looked at him. "You're using an engine designed to move planets to deflect asteroids."

"That's a simplified way of putting it."

"How dangerous is it?"

The man was honest. Jack appreciated that. "The consequences of failure cannot be predicted. They could be localized. They could be global. They could be — " He stopped. "Let's just say that we don't know."

Jack thought about this. "No."

The man did not look surprised. "Let us know if you change your mind."

Jack did not change his mind. The man offered him more money. Jack said no again. The man stopped offering money.

A different man, also in a suit, sat across from Jack. He did not offer anything. He simply told Jack that the woman — the one who had brought him the blueprints — her husband had not died in a car accident. He had tried to shut the engine down. He had thought it was dangerous. He had been wrong to think that. The people who operated the engine disagreed.

Jack thought about the woman. He thought about the blueprints. He thought about the radios he repaired every day — small, useless machines that people bought because they wanted to hear voices from far away.

He said yes.

He worked at the facility for three years. He never talked about it. He drank more. He stopped answering the woman's letters. He repaired radios on weekends, in his garage beneath the noodle shop, as if repairing radios could somehow make up for working on an engine that could push a planet out of its orbit.

One night, he stood in front of the engine and watched it run.

It was pushing against something — against gravity, against the orbit of the Earth, against the natural order of things. The rotation was slow but relentless. It was the kind of motion that made you think of Sisyphus, who pushed his rock up the hill for eternity.

The engine would never stop. It would run until the sun died or until something broke it. Jack was part of that. He was one of the people pushing.

He walked out of the facility into the California night. The stars were bright. He looked at them and thought about Sisyphus. The rock was the engine. The hill was the sky. Jack was the man pushing.

He got in his car and drove back to Los Angeles. He opened his garage. He picked up a radio and started repairing it. The radio crackled. A voice came through, distant and faint, like a voice from the other side of the sky.

Jack adjusted the dial. He could not make it clearer. He could not make it go away. He just kept turning it, turning it, turning it.

The rain fell outside. The city bled color onto the pavement. The engine pushed against the sky. Jack pushed against the radio.

Nobody won. Nobody lost. The rock went up the hill. The rock came down. The rock went up again.