On Tuesday the twenty-seventh, at twenty minutes to nine in the evening, Luke put on his coat and said that he had an appointment.

He said it from the doorway of the kitchen, with one arm already in a sleeve, in the light and neutral voice he used for the small facts of the day. Elias was at the table with a pot of tea and a journal of forensic pathology, and he glanced up, and saw the dark wool coat, and the gray scarf, and the shoes that had been polished that afternoon. He saw something else, too. It was in the set of the shoulders. It was a faint, tight, withdrawn quality, like a man preparing to lift something heavy.

"I shall be late," said Luke. "Please do not wait up."

"I will not."

"There is soup on the stove."

"Thank you."

"The door will lock behind me. You have the key." A pause. His hand was on the knob. "If you should need anything, you have my number."

"I have it."

"Yes." The faintest ghost of a smile. "I thought that you might."

The door closed. The lock turned. His footsteps went away down the corridor, soft and unhurried, and the elevator chimed, and Elias sat very still with his hands around the warm china and counted to sixty.

Then he put down the cup.

It had been ten days since he came. Ten days of tea and toast and quiet, of sitting across a scrubbed oak table from a man who set a place for him without being asked. He had learned the apartment as one learns the face of a stranger. The way the radiators knocked at six. The way the third stair of the back staircase creaked. The slow gold light that came through the east window in the early morning and moved across the floor to the foot of the sofa. He had learned, too, the rhythm of the man who lived there: the swim on Thursdays, the church on Sundays, the long silences over the dishes.

But he had never, in ten days, known him to go out on a Tuesday night.

He sat and thought about that. It was a very small fact. It might have meant nothing at all. And yet he found, turning it over, that it did not feel small. It felt like the corner of a card, protruding from beneath a pile of others, and when he looked back along the days, he could see a pattern beneath the pattern. The Tuesday that Luke had told him he would be working late at the office. The Tuesday of the stairwell, when Elias had lain on a laboratory floor and a man had come running. He had thought it chance. He had thought a great many things were chance.

He did not follow the thought. He put it where he put the others.

He rose, and crossed the kitchen, and stood in the dim passage that led to the back of the apartment.

The corridor was long and narrow and lit by a single low lamp at the near end. Beyond the lamp the floor ran on into shadow, past the linen cupboard and the bathroom and the plain white door of the room that was his, and ended in a wall of gray steel. It was very quiet. Somewhere in the walls a pipe ticked. The whole tower seemed to hold its breath.

He walked toward the door.

He went slowly, with his hands at his sides, listening to the soft sound of his own shoes. He did not know what he expected. Some part of him had half hoped, over the last ten days, that the thing would prove an illusion. That when he came to it at last, he would find an ordinary closet, with a mop and a vacuum cleaner and a broken chair. But the door stood there in the shadow, flat and gray and blank as a tombstone, and he stopped in front of it and felt the cold of the metal radiate against his face.

The keypad glowed.

It was a small black square, set into the wall at the height of his shoulder. Twelve buttons. A narrow window of dark glass above them, and in the corner a green light that burned steadily, like an eye that did not blink. He looked at the buttons. He had looked at them on his first morning, bending close, and seen the faint polish on three of them: the one, the zero, the six.

One. Zero. One. Six.

He had known it for ten days. He had known it as he knew the lines of his own palm. He had told himself that it was a certainty, a clear, cold fact, the sort of thing a man does not need to test. The sixteenth of October. A gray block on a calendar. A man who visited a grave once a year, and kept the date locked in a steel box.

And now he stood before it, with the whole apartment empty behind him, and his hand rose.

He did not remember deciding. The motion came of itself, the way one's hand rises to catch a falling cup. He saw his own fingers, in their black glove, move toward the panel. He pressed the one.

A soft electronic chirp. A tiny red dot flashed on the glass.

He pressed the zero. A chirp. He pressed the one again.

His heart was pounding. It was ridiculous. It was a plastic panel in a hallway, and he was a grown man of thirty, and he felt as though he stood at the edge of a roof. His finger hovered above the six. The air in the corridor seemed to thicken. He could hear the blood in his ears. He thought of a door opening, and a hand on his arm, and a voice saying: I told you that I would never open it unless I was invited. He thought of a man who had made that promise in a kitchen, with a dishcloth in his hand.

He pressed the six.

The panel was silent for a half second.

Then the green light flickered, and turned red.

A low flat tone sounded, a single dull buzz, like the note of a dying bell. The little glass window lit up, and a line of pale letters appeared across it, very small and very clear.

ACCESS DENIED. 2 ATTEMPTS REMAINING.

Elias stood perfectly still.

It was not the sound that struck him, or the red light. It was the arithmetic. Two attempts. There had been three. He had used one, and it had failed, and he had been so certain. It had not occurred to him that he could be wrong. He had taken it for granted, in the dark of a thousand nights, that the lock was a monument, that the number would be the same as the grave.

It was not.

He stared at the line of letters until they swam. He thought: it is not the date of the fire. It is not the sixteenth.

Then what is it?

It seemed to him that something large and cold had turned over in the depths of the water. He had been so sure. He had built a structure on that certainty, a long careful staircase of inference, and it had gone out from under him in a single note. He did not know the man. He had thought that he did. He had read the file, and the calendar, and the face, and he had put the pieces together into a shape that he could hold. And the shape had been wrong.

He lifted his hand. It was shaking. He pressed it against his chest, and stood there with his heart hammering, and for a moment he could not think at all.

Then, slowly, as one counts through a list of suspects, he began to try the others.

The date of Luke's birth. He knew it, from the department record: the ninth of March, thirty-five years ago. It was the first thing that anyone would try, and it was not the sort of thing that a man like that would use. The date of his graduation from the academy. The date of his promotion. The number of his badge, which was four digits, and which Elias had memorized at the age of nineteen for no better reason than that it was in front of him. The date of his mother's birth. The date of his father's death.

He turned them over and over, like coins in a pocket. Each of them might be right. Each might be wrong. And the machine behind the door had been very clear. Two more. Two, and then a lockout, and perhaps an alarm, and certainly a record, and in the morning a quiet question over breakfast that he could not answer.

He lowered his hand.

He had no right to the guess. He knew that. It was the guess of a man who had been wrong once and could not afford to be wrong twice. He stood in the dim corridor and felt the whole weight of his own ignorance settle on his shoulders like a coat.

He backed away.

He did it step by step, not turning, with his eyes on the red light. It faded slowly. After a few seconds the glow changed to a soft pulsing amber, a little patient flicker, like a lantern in a window, and the letters on the glass dimmed and went out. The panel said nothing more. It did not need to. It had recorded him. It would go on recording him, in its little amber breath, until someone came and reset it.

He turned, and walked back down the passage, and did not look behind him.

He sat in the kitchen until one in the morning.

He made tea. He drank it. He made more, and let it go cold. He washed the cup, and dried it, and set it on the rack with the handle turned outward. He sat down again at the table with his hands folded on the wood, and watched the clock above the door.

Ten. Eleven. Midnight.

It was a clock in a white plastic case, with a plain black second hand that moved in small jerks. It ticked very loudly in the silence. He did not like it. He sat and listened to it count out the minutes of a night he could not sleep through, and thought about where the man was.

Not a lover. He could dismiss that at once. A man who looked at a table of strangers with such fixed patient tenderness, who stood at a doorframe for ten minutes without crossing the sill, was not a man who went out on a Tuesday to meet a woman. Not a bar, either. Luke did not drink. He had seen the man at a gala with a single glass of water in his hand, all evening, and a half-smile for every waiter who offered more.

Not a case. A case would have had a number, and a file, and a phone call in the afternoon.

He had gone out like a man going to church.

It came to Elias slowly, in the long hour past midnight, with the radiators knocking in the walls and the city lights lying pale on the ceiling. He thought of a wind on a telephone line, and a faint crunch of gravel, and a voice that said, a place I go once a year. And he thought: once a year is the date. But a man who has a grave does not visit it only on the day. He goes on Tuesdays, too. He goes on the nights when the loneliness is too great to bear in an apartment with a view.

He is going where he always goes, he thought.

He did not say the name of the place, even to himself.

At twenty past one, he heard the lock.

It was a soft sound, a quick dry click, and the door of the apartment swung open on the dark. Elias did not move. He sat at the kitchen table with the lamp burning at his elbow and the cold tea at his hand, and listened to the footsteps come in.

They were slower than usual. They crossed the hall, and stopped. A coat was shed, with a rustle, and hung on a hook. A scarf. A pair of shoes was set down side by side on the rack, very quietly, as a man sets them down who does not wish to wake the house. Then, after a moment, the steps came on, down the length of the dark hall toward the kitchen.

He smelled it before he saw him.

It came into the room ahead of the man, a faint dry smoky sweetness, like the memory of a fire. Wood smoke. Old and cold and damp, the kind that lives in plaster and rafters for years after the flames have died. It was threaded with something else: a mineral, ashy edge, the smell of burnt beams that have been rained on, and underneath it all the clean sharp scent of wet stone. It was a smell that Elias would have known in the dark. He had not smelled it in twelve years. It reached him across the kitchen and struck him in the chest like a fist.

Luke stood in the doorway.

He had not turned on the light. He stood in the dimness of the passage with one hand against the doorframe, and the amber glow from the end of the hall lay behind him like a halo. He was in his shirtsleeves. His hair was damp. There was a smear of gray on the cuff of one sleeve, a faint pale dust like powdered chalk, and the knees of his trousers were wet through.

He looked at Elias.

He did not seem surprised. That was the first thing Elias noticed. His face in the dimness was pale and tired and perfectly still, and his eyes went from the lamp to the cold cup to the folded hands on the table, and settled on Elias's face without a flicker. It was the look of a man who had expected to find exactly what he found.

His gaze moved, very slightly, over his own shoulder.

Down the long dark corridor, at the far end, the little panel glowed amber in the wall. It pulsed softly. It pulsed like a heart.

Luke turned his head back.

Neither of them spoke.

It was the longest silence that Elias had ever known. It stretched across the kitchen like a taut wire, thin and bright and trembling, and he sat motionless in its center with his eyes on the other man's face. He could hear the clock ticking. He could hear his own pulse in his throat. A truck passed, far below, in the street, and the sound rose and faded like a breath.

He knew that Luke knew.

He knew it with an absolute and quiet certainty, in the very bones. The man had come in through the door, and passed the amber light, and seen it. He knew what it meant. He knew that a hand had touched his lock, and that it had been the hand of the only other person in the house, and that three digits had been entered and a fourth had been wrong. He knew everything. And he stood in the door of the kitchen with the smell of ashes in his clothes, and did not say a word.

Elias did not look away.

He had thought that he would. He had thought that he would drop his eyes, or speak, or rise. He had imagined a dozen ways of falling out of this moment, with a cough or a lie or the clatter of a cup. But he sat quite still with his gloved hands folded on the oak, and held the dark gaze, and let it hold him.

It was not accusing. That was what undid him. He had expected anger, or hurt, or the cold look of a man who has been betrayed. But the face before him held nothing of the kind. It was only open. It was bare, and tired, and grave, and in the depths of the dark eyes there was something very strange. It looked, he thought, almost like gratitude.

Not gratitude that he had tried. Gratitude that he was still here.

The kitchen seemed to grow warm.

He did not know how long it lasted. A minute. Two. The clock ticked on. The amber light pulsed at the end of the hall. Neither of them moved, and neither of them spoke, and the whole room hung in a sort of breathless suspension, like a drop of water at the end of a leaf.

I know what you are, he thought.

I know where you have been.

I tried your door.

He could not say it. He could not say any of it. He sat with his lips closed and let the silence say it for him, and across the room, with something very like grief, the man in the doorway received it, and nodded, very slightly, as if he had been answered.

At last Luke moved.

He took his hand from the doorframe. He straightened. It was a slow, heavy motion, like a man lifting a weight he had set down for a moment, and he stood for a second in the amber half-light with his arms at his sides and his face in shadow.

"Good night, Elias," he said.

His voice was very soft. It was hoarse, and a little frayed, and it carried no reproach at all.

"Good night."

He turned. He walked down the passage with his slow unhurried tread, and passed the white door of the room that was Elias's, and the linen cupboard, and the bathroom, and went on into the dim. Elias heard him stop. It was at the far end, near the wall, where the amber light was. The footsteps ceased.

He did not hear the panel chirp.

He did not hear the door. There was only silence, and then a faint, quiet sound, like a man drawing breath. And then the steps went on, a pace or two, and a door opened and closed. It was the bedroom door. It shut very softly.

Elias sat alone in the kitchen.

He sat for a long time. The tea had gone quite cold. The clock ticked. The lamp burned on, and the pale light shifted a little on the wall, as it does when a cloud passes in front of the moon. His hands, folded on the table, had begun to tremble, and he looked at them for a while with a sort of distant interest.

It was past two when he rose.

He walked down the passage as far as the door of his room. He stopped there, with his hand on the knob, and looked back along the length of the corridor. The amber light was still burning at the end of it, small and steady, in the shadow of the gray steel door.

Luke had left it.

That was what he understood, standing there in the silence. A man who locked his study with a steel door and a three-try keypad would not have let a failed attempt stand. He would have reset it at once. It took a single key, a moment of work, the sort of thing a man does without thinking. But he had walked past it, and not touched it, and gone to bed. He had left the little light burning, where it would be the first thing seen in the morning.

He had left it for Elias.

It was not a rebuke. It was not a trap. It was the thing a person does when he wishes to say, I know, and I am not angry, and I will not pretend that nothing has happened. It was a candle in a window. It said: this is the lock. This is what you tried. I am not hiding it from you.

I am only not yet able to open it.

Elias stood with his hand on the knob, and found that his eyes were stinging.

It was absurd. It was nothing. A light in a corridor. But he stood there in the shadows of a stranger's house, in the small hours of a Wednesday morning, and looked down the long dark hall at a glowing amber dot, and felt something go through him that he had not felt since he was a boy. It was a hard, sweet, intolerable ache, and he could not tell if it was grief or something else.

He went into his room. He closed the door.

He did not turn the key.

He lay down on the bed with his clothes on and his gloves on and his hands folded on his chest, and he looked at the ceiling. The window showed a square of pale gray sky. From the far end of the apartment came the sound of a man turning over in his sleep.

He did not sleep. He lay and watched the light change, slow and gray and cold, and listened to the old faint ticking of the radiators, and thought about a smell.

Smoke. Wet ash. A wall of old stone, rained upon.

He had stood in that house when it was whole. He had run through its hall as a boy, and slid on its waxed floors in his stocking feet. He had sat on the stairs in the dark, listening to his father's voice through the study door. He knew every board of it. And he knew, as clearly as if he had been standing in the ruins himself, what the man in the next room had been doing for the last five hours.

He had been sitting in the dark, in the wreck of a burned house, with his back against a blackened wall.

Not for a case. Not for a plan. Only because it was Tuesday.

He closed his eyes.

He lay there while the light rose, and thought of the knees of a pair of wet trousers, and a smear of gray on a cuff. He thought: he goes there, and he kneels. And then he comes home, and he leaves a light for me.

He did not know what to do with that.

It was a long time before it grew bright. When it did, there was a small sound at his door, very soft, a creak, a breath. He lay still. There was a pause. Something was set on the floor outside. Then the footsteps went softly away.

When he opened the door, an hour later, there was a cup of tea on the boards. It was still warm. And the amber light, at the end of the passage, had been left to burn.