He found the first fault in forty minutes, the second by Wednesday night, and the third at a quarter past four on Thursday morning, in the bath, with the water gone cold around him and a sentence from page six turning over and over in his head.

The plan was good.

And it still had three holes in it.

"The guard," he said, on Wednesday evening.

They were in the kitchen. Luke sat at the end of the table in a gray sweater with his elbows on the wood, and he had not spoken for an hour. He had brought tea at six, and again at eight, and set the cups at the edge of the lamplight without a word, and gone back to his chair. He had watched Elias work with an expression that Elias did not look at too closely. It was very still.

"There is one man on the night shift," Elias went on. "A retired fireman, named Dwyer. He is sixty-three. He makes his rounds at midnight and at four." He turned the page. "Your schedule has us in the building from ten past one to a quarter to two. A very comfortable margin. But Dwyer's relief is a young man, on Fridays and Saturdays. A student, of the night school. He is not on your list."

"I have not known of a relief."

"He is on the roster for the twenty-eighth. It is in the building's own log. I have a copy." He tapped a sheet. "He changes the round. He does it at two instead of four, because he wishes to study. He is conscientious. He is also, I should think, much quicker on his feet than Dwyer."

Luke's face did not change. He took up a pen, and wrote a line in the margin of his own copy of the plan, in his square black hand. He did not argue. He did not so much as lift an eyebrow. He wrote it down as a man notes the address of a dentist, and said, "That is one."

"Yes."

"I shall move the window forward by forty minutes."

"You will move it forward and shorten it. Fifteen minutes in the building. No more." Elias lowered his eyes. "The longer a thing takes, the more can happen to it."

"Yes."

The second came the next night.

It was in the section on the corridor, which Luke had described in four neat lines, and which Elias had read nine times before he saw what was missing. It was the stairwell. The floor plan showed it plainly, on the back of the second sheet, a narrow concrete shaft that ran from the basement to the roof. Luke had planned to use the lift. He had written, in the plan, that the lift was quiet, and slow, and kept no record.

"It keeps a record," said Elias.

"It does not. I checked."

"You checked the maintenance schedule. You did not check the access. There is a card reader in the car, on the control panel. It was installed in September. It logs each use against the card that opens it." He laid down a photocopy. "It is in the building's insurance inspection. The company that fitted it wrote a report. It is a very dull report. It is in the public file."

Luke took it.

He read it slowly. Elias, who was watching, saw the thing that happened in his face. It was not alarm, and it was not annoyance. It was a faint, bright, almost joyful look, like the look of a man who has been shown a better road. He lifted his eyes.

"We take the stairs."

"We take the stairs."

"Eight flights."

"I should think we can manage it." Elias felt his mouth move, unwillingly. "You swim on Thursdays."

"So I do."

The third fault was the worst.

He found it at a quarter past four in the morning, in the bath, as he had known that he would. There were certain kinds of thing that he could not see with a pencil in his hand. They came to him in the dark, in warm water, in the middle of some other thought, and lay still until he turned his head. He sat in the cooling bath with his knees drawn up and his arms about them, thinking of nothing at all, and a line from the sixth page rose in his mind like a bubble.

The key.

The plan said that Luke had a key. It said it in six words, in the middle of a paragraph about the vault, in the flat dry style of a man noting a thing that has been settled. The second key. Obtained previously. And Elias had read it, on Wednesday, and passed over it, because it had no particular weight.

It had a great deal.

He sat there in the water, and the whole of it came clear. A vault with two locks is a vault in which neither of two men can act alone. It was the point of the thing. The firm kept one key. The bank, or the company, or the archives, kept the other. And the box that Luke wanted, number 114, had belonged to Martin Osgood. It was Osgood's. It would open for him, and for his partner, and for no one else.

Martin Osgood was dead.

He had been dead for eleven weeks. He had been a blue and waxen thing on a table, with a numeral on his chest. His effects had been bagged and tagged, and carried to the evidence room on the second floor of Blackwood Police Department, and logged, and locked in a cage. A set of keys. A wallet. A pen. And on the ring, among the others, small and brass and ordinary, a key that opened a box in a vault by a river.

Luke had it.

Elias did not know how he knew. He only knew, with the cold clear confidence of one who has found a flaw in a wall and recognizes in the same instant that the wall was built to be found. A key that was in evidence could not be in a pocket. Evidence was signed in and out, and numbered, and watched. If it had been taken, there was a record. And the record was a thread. It ran from the cage on the second floor to the dark in the vault, and at the other end of it, patient and unhurried, sat the man who had done it, and the whole of the plan depended upon nobody ever pulling.

He got out of the bath.

He dried himself, and dressed, and went down the passage in the dark. He found the man in the kitchen, at the oak table, with a cup of tea and the lamp lit, and he knew that Luke had not slept either.

"The key," he said.

Luke did not look up. He had been looking at the wood. His shoulders had gone a little rigid.

"I wondered whether you would find it."

"It is in the evidence room."

"It was."

"You took it."

"Three weeks before you had told me anything."

"Five."

"You planned it before you knew that I would read the plan."

"I planned it before I knew you would read anything." His voice was very low. "I thought that I would do it alone. I had thought so for twelve years. And when Osgood died, and I had his keys in my hand, I thought, here it is, here is the one thing that I have not been able to reach, and I did not sleep for a week." He pressed his lips together. "I did not know that you would come. I made a copy because I could. I did not know what I was keeping it for."

Elias stood in the doorway in his stocking feet.

"It is the third fault," said Elias.

"Yes."

"If the evidence log is ever audited. If anyone ever asks what became of a key to a box in a vault, and compares the dates, and sees that a captain of Major Crimes was in the cage on a Sunday in October." He drew breath. "You will have to have a reason."

"I shall have one. I have not yet thought of it."

"I have."

Luke looked up.

"There was a request," said Elias slowly, "on the fifth of October. For a review of the Osgood inventory, by the Chief Medical Examiner, as part of the toxicology work on the second victim. It was filed in the ordinary way. It is in my own name." He swallowed. "I filed it myself. It is on the system. It gave me access to the cage for a week, on any day, for any purpose connected with the case. I did not use it. I never went down."

"You did not."

"But no one will ask whether I did."

It lay between them.

"I shall say that I asked you to fetch it," he said. "If it comes to that. For the toxicology. I shall say that I sent you for the keys."

"Elias..."

"It is the story. It will do."

Luke bowed his head.

He did not say thank you. He had said it so often that it had worn a groove in the air. He only sat quite still with his hands on the table, and Elias, who had been standing in the cold, crossed the floor and sat down at his own place, and drew the plan toward him, and uncapped his pen.

"Show me the vault again," he said.

On Friday night the whole of the city ate turkey, and Calder Secure Archives stood empty on the river like a tooth.

Elias had not seen it before. It was an old brick warehouse, five stories high, black with a century of soot, on a spit of land below the Marlowe Bridge where the road gave out. A single sodium lamp burned on a pole at the corner. The water lapped at the pilings. A chain-link fence ran around the whole, tipped with wire, and in the fence was a gate, and beside the gate a small square box on a post. It was one in the morning. It was very cold. A sliver of moon lay on the black water, and the wind off the river smelled of ice and diesel and a long way off.

They had parked a quarter of a mile away, beside a closed boatyard, and walked.

They did not speak. They had agreed on that. They walked along the verge in the shadow of the fence, side by side, a foot apart, in dark coats and dark caps, with their hands in their pockets and their breath going up in the lamplight like smoke. Luke walked a little ahead. He moved without hurry. He did not look around. He moved like a man going home, quite certain of the door, and the confidence of it was so entire that Elias, a pace behind, found that his own heartbeat had slowed to match it.

He had expected, with every nerve, to be afraid. He was not. What he felt, walking in the freezing dark beside the river, with a plan in his head that he knew by heart, was a clean, still, extraordinary attention.

Luke stopped at the gate.

He took from his pocket a small white card, plain and unmarked, and held it a moment in his gloved hand. He did not look at it. He looked at Elias. His eyes in the dim were dark and clear and very steady, and there was in them a question so plain that it did not need to be asked.

Elias nodded.

The card touched the reader. A small green light winked. The gate gave a soft clank, and slid open on its track.

The building was cold.

It was the cold of stone and iron, and of a great many closed rooms. Their feet made no sound on the concrete floor of the loading bay. A single caged bulb burned over the door, and beyond it the dark went back and back, in long aisles of steel shelving, stacked to the ceiling with gray cardboard boxes. The air smelled of dust and old paper and the faint sweetness of mildew. A long way off, somewhere at the end of the hall, a radio was playing very low. It was a ball game. It was the sound of a man, in a small lit room, in the middle of a holiday weekend, with a thermos and a book.

Luke put a finger to his lips.

They went up by the stairs.

At the eighth he stopped.

It was a steel door, painted gray, with a small wired window set at the height of a man's face. He drew himself against the wall beside it, with the stone cold against his shoulder, and heard Luke breathe at his side, slow and soft and even. A faint pale light came through the glass. There was no sound beyond it.

Luke held up his hand, and showed three fingers, and then two.

He pushed the door.

It opened on a long corridor, lined with doors of its own, narrow and gray and numbered in white paint. It was lit by a single row of small lights set into the ceiling at intervals, each one no brighter than a candle. At the far end was a larger door, of steel, with a great circular wheel at its center like the hatch of a ship.

The vault.

At the end, Luke stopped.

He did not touch the wheel. He drew from his coat, quite slowly, a small brass key on a ring. It caught the light, and glinted. He held it up between them, for a moment, between finger and thumb, as one holds up a thing that one is not quite sure one believes.

It was twelve years old. It was the only thing in the world that did not belong to him.

"Together," said Luke.

It was only a breath.

There was a second lock, on the wall at the right, a plain brass keyhole in a steel plate, at the height of a man's chest. Luke fitted the key to it. It went in with a small clean click. He did not turn it. He looked at Elias, and held out his other hand, palm up, empty.

For a moment Elias did not understand.

Then he did. It was the thing that Luke had said in the kitchen, on Tuesday, in a low voice, bent over a page. I should like it to be done by both of us. It is your father's. I should like you to turn the key. He had said it so simply that Elias had thought it a figure of speech. It was not. It lay in the open palm, in the cold light of a corridor, a bare plain offer.

He put his gloved hand over the other's, on the key.

It was warm. He felt it through the leather. A hand beneath his own, large and steady, and beneath that a small brass shape, and the heavy faint tension of a lock waiting to be turned. He did not speak. He did not breathe. He felt the other's fingers close around his, lightly, and together, with no more force than it takes to turn a page, they turned.

The bolt slid back.

The wheel moved under Luke's other hand, with a long slow groan of iron, and the vault door swung inward on its hinges, and a breath of colder air came out, smelling of dust and old leather and something sweetish. A light came on, by itself, a pale yellow bulb in a wire cage. And there before them, in two long walls of small steel doors, set in neat rows from floor to ceiling, were the deposit boxes of the dead.

It took four minutes.

Number 114 was on the left, at the level of Elias's eyes. It had a plain brass plate, with a name stamped on it. O & P. Luke touched it with the pad of one finger, and did not speak. He took a second key from his breast pocket, a different one, small and gray. It had been in the dead man's overcoat. He fitted it to the lock.

The door swung open.

The box was a long steel drawer, a foot deep and two across. He drew it out with both hands and laid it on the narrow shelf that ran along the wall. He lifted the lid.

Inside were two things.

One was an envelope. It was a thick brown one, of the heavy manila kind that lawyers use, sealed with red wax and tied about with a length of white tape. It had a number on it, in ink, and a date. It was Osgood's own. It was the small private insurance of a frightened man.

The other lay beneath it.

It was a book.

It was a small, plain, thick book, about the size of a man's palm and rather more than an inch in depth, bound in black leather gone brown at the corners. The spine was cracked. A strap of the same leather, worn thin, was buckled round its middle. It had no title. It had no mark. It lay in the bottom of the steel drawer under a sheet of tissue paper, like a thing in a reliquary, and the pale light of the bulb lay along its cover without a sound.

Elias stood looking at it.

He knew it.

He had never seen it. He was quite certain that he had not. But he knew it, with every fiber, as one knows a voice in the dark. It was the book that his father had carried in the inside pocket of his overcoat, over the heart, every day of his life, and called his sketchbook. It was the book that he had laid on the kitchen table, on Sundays, and written in while Elias did his sums, with the small neat figures that went up the page like stairs. It was the book that had never once, in eighteen years, been opened in a child's sight.

It had been a boring one. He had said so.

It was not his to lift.

Elias put out his hand.

It was a very small movement. It took the whole of his strength. He laid the tips of his gloved fingers against the leather, lightly, as one touches a face. It was cool and dry and a little rough, and it gave very slightly under the pressure. He drew it from its tissue. It was heavier than he had thought. It lay in his two hands like a thing that had a heart.

"It is here," he said.

His voice cracked.

"Yes," said Luke, very softly.

"It was here all the time."

"Eleven years in a box. And a year before that in a drawer." The voice was a thread. "I am sorry that it took so long."

Elias did not answer.

He held it against his chest, in both arms, and bent his head over it, and stood for a moment quite still, in the pale light of a vault, among the boxes of the dead. A small sound went through the corridor. It was a long way off. It was the sound of a door.

He lifted his head.

Luke's face had altered. It had gone perfectly still, and white, and blank. He had turned his head, a little, toward the stairs, and every muscle of his body seemed to listen. Elias heard it too. It was the faint hollow clang of a steel door, and after it, quite distinct in the stillness, the slow echo of a footstep on concrete.

"The round," breathed Elias.

"Early."

"By an hour."

"He is the student." Luke's hand closed on his arm, quick and hard, above the elbow. "Close it. Quickly. The envelope."

Elias had the book in his coat. He did not know how. He shoved the box back into its slot, with a small flat clang that rang in the vault like a shot, and the envelope went into Luke's breast, and the little door was locked, and the key was in his pocket. He felt the cold sweat spring out on his back.

"The lamp."

"It will go out when the door closes."

"The door."

"Now."

They moved.

They went back through the vault door in two strides, and Luke swung it to behind them, and heaved the iron wheel round, and the bolt shot home with a sound that seemed to go on forever. The light in the vault went out. The corridor was dark. Down the length of it, round the turn, a small yellow circle of torch was swaying slowly along the wall.

"Here," said Luke.

He pulled Elias against him.

It was a doorway. It was a recess in the wall, no more than two feet deep, where a fire hose had once hung. The door beside it was a blind one. It was perhaps three feet wide, and just deep enough for a man, and Luke thrust him into it, backward, and turned, and set his own broad body in front of him like a plank across a hole.

They stood chest to chest.

Elias could not move. His back was against cold plaster, and the whole of the other man pressed against him, from knee to shoulder, warm and hard and utterly still. He could feel his breath, brief and hot on his forehead. He could feel the long muscles of his arms, braced on either side. A hand lay flat against the wall beside his head.

The footsteps came on.

They were young and quick and a little uneven. They came down the corridor in a slow regular rhythm, and a beam of light swung ahead of them, across the floor, and up the wall, and over the vault door. It was a small flashlight, held low. It touched the iron wheel. It lingered. It moved on.

Elias felt a heartbeat.

It was under his hand. He had put it up, without knowing, in the cramped dark, and laid it flat on the other man's chest, over his coat. It was beating very hard. It was going like the wing of a trapped bird, fast and light and heavy at once, and it shook his palm. He could feel it through two layers of wool. And over it, steady, a long slow breath, drawn in through the nose and let out through the lips, in a rhythm so careful, so deliberate, that he understood, with a shock, that the man was counting.

He is afraid, he thought. He is terrified.

He had not thought that Luke Harrow could be.

The beam swept the wall a foot from Luke's shoulder.

Neither of them breathed.

The footsteps stopped.

A long, long moment. A cough. The faint rustle of a coat. A muttered word, bored and sleepy, and then, from far down the corridor, a thin electronic voice squawking out of a radio. The footsteps resumed. They turned. They went back the way they had come, unhurried, not looking, with the swinging light.

They went round the corner.

They faded. A door clanged. The sound of a round being completed, on a cold night, by a boy with his mind on an examination, went slowly away into silence.

Luke let out a breath.

It was a shuddering, ragged thing, and it blew warm against Elias's cheek. He had not moved. His hand still lay against the wall, and his body against Elias's, and his forehead had dropped, very slightly, until it rested against the plaster beside Elias's ear. He was shaking. It ran through him in fine quick tremors, from the shoulders to the knees.

"Luke," whispered Elias.

"I am all right."

"You are not."

"No." A short unsteady laugh. "I am not. I thought that, I did not, for a moment I thought." He did not finish. He lifted his head. His face in the dark was a pale blur, and his eyes were enormous. "I could not have borne it if they had found you."

"They did not."

"No."

"Nobody was hurt."

"No." The hand left the wall. It came down, slowly, and closed on Elias's, the one that still lay on the beating chest, and held it there. "Nobody."

They went down the stairs together, with a book in a coat and an envelope in a breast, and a small brass key between them, and did not speak.

In the car, he held the book on his lap.

Elias had unbuckled the strap.

He did it with his gloved fingers, very carefully, in the dim glow of the dashboard, as one opens the eyelid of a sleeper. The leather was stiff. It gave with a faint dry creak. The cover fell back. The first page was a flyleaf, plain, cream-colored, soft with age. It held a single line, in ink, in the middle of the page.

T. A. Mercer. Private. Please return.

It was in a hand that he knew.

He had seen it on a hundred notes. On the back of a school report, in the corner of a birthday card, on a slip of paper under a magnet on the door of a refrigerator, saying: Back at six, there is soup. It was a slanting, quick, kindly hand, with a long tail on the y and a small flourish on the capital. It was his father's. It had been written, in a chair, in a lamp, with the cap of a pen between his teeth. And somebody had folded it, and stored it, and kept it in a box in the dark for twelve years.

Please return.

He made a sound.

It was not loud. It was a small broken sound, drawn in through the nose, and he put his gloved hand up to his mouth and pressed it there. He did not turn his head. He sat with the book open on his knee and the dashboard light on the page, and the tears ran down his face without any effort at all, silently, in two clean tracks. He did not wipe them. He let them fall on the leather glove, and the cuff, and the flyleaf.

Luke did not speak.

It was the finest thing that anyone had ever done for him.

At the corner of the river road, under a lamp, Elias drew a long uneven breath.

"No one died," he said.

His voice was thick.

"No one."

"Good."

"Yes."

They drove on in silence for the length of a block. The tires hissed on the slush. The snow blew in small white wreaths across the beam of the lights.

"I was afraid," said Elias.

"Of what?"

"That you would not be."

He heard the breath go out of the man beside him, a short soft sound that might have been a laugh. The hands tightened on the wheel.

"I was afraid the whole night," said Luke.

It was a very low voice.

"I was afraid when I put the key in the lock. I was afraid in the stairwell. I was afraid in the corridor, with you at my back, and I have not been so frightened in my life." He swallowed. "I have done a great many things in the dark, Elias. I have done them with a very steady hand. And I have never once been afraid. It is how I knew that I could." A breath. "And tonight I was afraid every minute. I think that it is because I had something to lose."

Elias closed the book.

He closed it slowly, with both hands, and laid it on his knee, and held it there. He did not look at the road. He did not look at the man. He sat in the warm dark of the car, with the dashboard glowing, and thought that he had never been so tired, or so sure, or so entirely and helplessly in love.

He did not say it.

He put out his hand, instead. It was bare. He had taken off the glove, in the dark, without noticing, and now he laid his hand on the gear lever, on top of the other man's, and held it there. Luke did not speak. His fingers turned, under his, and closed. They drove like that, through the whole of the white and sleeping city, with the heat blowing and the snow coming down, to the foot of a tall black tower on a hill.