At eleven minutes past two, Yeon Haeseul wrote the number in the small green notebook she kept under the register, and then she closed the notebook before anyone could see it.

Two hours and forty minutes. That was how long she had slept the day before, if she counted the part where she had been lying on the sofa with the television murmuring and her eyes closed and her mind running through the inventory list for the tenth time. A pharmacist ought to know better. A pharmacist could have recited, without opening a book, what a body did when it was starved of sleep for years: the slowed reflexes, the thin tempers, the small cruel lapses of memory. Haeseul knew all of it, and she wrote down the number anyway, night after night, the way some people press on a bruise to check that it is still there.

Dawnbridge Pharmacy stood halfway up a steep street in the old part of Haeryeong, where the harbor lights climbed the hill in uneven rows and the sound of the sea reached the pavement only as a low, patient breathing. It was the only pharmacy in the district that stayed open all night, and that was the reason Haeseul had taken the late shift six years ago and never asked to leave it. By day the place belonged to the crowd: mothers with feverish children, fishermen's wives with prescriptions, students buying vitamins they would forget to take. By night it belonged to the lonely. The night people came in with different faces. They were nurses coming off long shifts, taxi drivers with aching backs, widows who could not bear their own kitchens, and the occasional young man holding a hand over a cut he had been too proud to show anyone.

Haeseul liked them. She would not have said so aloud, but she liked how the dark made people plain. At three in the morning nobody bothered to arrange their expressions. They simply told her what hurt, and she told them what might help, and for a few minutes the space between the shelves was as honest as any place she knew.

"Noona, you are doing the face again."

Han Gyeol was sitting on the step stool beside the vitamin display, a cardboard box of cough syrup open between his knees. He was twenty-three, a pharmacy student on his placement year, with a round, earnest face and a habit of narrating other people's moods as though he were a very polite weather forecaster.

"What face?" Haeseul asked.

"The one where you look like you are counting something."

"I am counting the cough syrup. You have shelved the same bottle three times."

Gyeol looked down at his hands with sincere alarm, and Haeseul let herself smile. It was a small smile, easy and tired, and it was the most honest thing she had done all evening. The boy was a good one. He asked too many questions and he apologized too often, but on the first night of his placement he had stayed forty minutes past his shift to help her carry a drunk man's wife through the door, and she had decided on the spot that she would keep him.

"Go on," she said. "Do the second shelf and then take your break. You look worse than I do."

"That is not possible, Noona."

"It is entirely possible. I have a mirror."

He laughed, and the sound filled the narrow aisle, and for a moment the pharmacy felt like exactly what it was: a bright, humming box of white shelving and green crosses, with the sleeping city all around it and two people inside who had agreed to keep the lights on.

She straightened the receipt roll. She wiped the counter, which did not need wiping. She turned the cream cardigan she wore over her white coat so that the cuff, which had begun to fray, rested out of sight. Her hair, long and dark and unwilling to lie flat, was tied at the nape of her neck with the same plain band she had used for three years. On her right hand, the silver ring that had belonged to her mother turned slowly when she was thinking, a small habit she had never managed to break. She did not know that she was doing it until the ring had made a full circle.

Her mother had died in the spring of her twenty-seventh year. Haeseul did not think about it at the register. She had trained herself, with great discipline, to leave certain rooms of her mind shut during working hours, and what lay behind that particular door was a long, gray corridor of hospital chairs and morphine charts and the sound of a person learning to breathe less. She had stayed in that corridor for the better part of four years. When she finally walked out of it, she found that the woman who had loved her, Lim Soojin, had walked out sooner, with a gentle apology and a single sentence that had lodged in Haeseul like a splinter under the skin. You are so tired all the time, Haeseul. It is hard to be near.

It had been true. That was the worst of it.

At a quarter to three, the lights flickered.

It was not a dramatic flicker. The fluorescent tubes dipped, the way they sometimes did when the harbor wind pressed against the old wiring, and then they steadied. Haeseul glanced at the ceiling out of habit and made a mental note to ask the landlord again. When she looked down, Gyeol had stopped moving.

He was standing very straight in the middle of the second aisle, one hand still resting on a shelf, his head tilted a little to the left, as if he were listening to someone speak from a long way off.

"Gyeol?"

He did not answer.

"Han Gyeol."

"Do you hear that?" he said at last. His voice was quiet and strange, as though he had been woken from a doze.

Haeseul listened. She heard the refrigerator hum behind the counter. She heard the faint tick of the wall clock, and, beyond the glass, the whisper of the wind among the signboards. "I hear the fridge," she said. "And the street."

"No," Gyeol said. "Under it. It sounds like someone breathing out. A long breath. Like a person who has been holding it for years." He turned toward her, and in the white light his face looked very young and very frightened. "It has been getting louder all week, Noona. I did not want to say."

A chill went across the back of her neck, delicate as a fingertip. She told herself it was the draft.

"You are tired," she said, and she made her voice the gentle, even voice she used for patients. "You have been working too many nights. Sit down. I will get you some water."

She had filled a paper cup at the dispenser and was carrying it down the aisle when the bell above the door rang.

It was a plain brass bell, and it rang the way it always did, one bright note, and yet something in the sound made her look up quickly, as though it had called her by name.

A woman stood on the threshold.

She was perhaps thirty, or a little older, and slight in the way of someone who has been working a long time without eating properly. Her black hair was cut short and blunt at the jaw, and the wind had pushed it across her forehead. She wore a thin gray jacket, much too thin for an October night by the sea, and underneath it a faded shirt with the sleeves rolled to the elbow. Her forearms were pale and corded and dark at the fingertips, as if she had been handling oil or ink. She was holding the doorframe with one hand, and Haeseul saw the hand tremble, very slightly, and then saw the woman notice it and press her fingers harder against the wood until the trembling stopped.

Her face was striking in a way that took a moment to place. It was not that it was beautiful, though it might have been. It was that it was so carefully held. Every line of it had been put in order by someone who had done it every day for a long time, and under that order, like water under a sheet of ice, there was something raw and exhausted and unbearably alert.

Her eyes found Haeseul across the length of the shop and stopped.

It was only a second. Haeseul would turn it over many times afterward and never be able to make it longer than a second. But in that second the woman's face changed, a small, terrible, involuntary change, the look of someone who has been walking a very long road in the dark and has suddenly seen a lit window. Then the ice closed over it, and the woman stepped inside and let the door swing shut behind her.

"Good evening," Haeseul said, because that was what one said. "Or good morning. Can I help you?"

"Yes." The voice was low and a little rough, and each word arrived as if it had been weighed first. "I need something to sleep."

"Of course. Is it for occasional trouble, or something you have had for a while?"

"A while."

"How long is a while?"

The woman considered her. "Three years, in the way that matters. Longer, if you count the years before."

Haeseul set the water on the counter and went around it. She had long ago learned that the best way to talk to a person at the edge of exhaustion was to give them something to hold, so she took a clean cup, filled it from the dispenser, which ran warm, and held it out.

"Please," she said. "You are shivering. It is only water, but it is warm."

The woman looked at the cup for so long that Haeseul wondered whether she had offended her. Then she took it with both hands, carefully, as if it might be taken away again, and drank. Her throat moved. Her eyes closed briefly. When they opened, she was looking at the sleeve of Haeseul's cardigan, the cream wool with its fraying cuff, and something crossed her face that Haeseul could not read at all. It was not pity and it was not curiosity. It looked almost like recognition, and almost like grief.

"Thank you," the woman said.

"You are welcome." Haeseul crossed to the shelf of sleep aids, took down two boxes, and began to explain them in the flat professional tone that was her armor. "Most of these work on the same principle, a mild antihistamine, and they are safe for short use. I would not recommend them for something you have had for years. For that, I would suggest seeing a doctor, because there may be an underlying cause, and honestly the pills will only..."

"They will not work on me."

Haeseul stopped. "I beg your pardon?"

"They will not work," the woman said again, evenly. "I only wanted to hear you say what they were."

It was a strange thing to say. Haeseul would have been annoyed, from another person, on another night. But the woman said it without any mockery, with a kind of tired candor, and she was still looking at Haeseul with that long, careful, attentive gaze, as if Haeseul were a clock whose mechanism she was trying to read.

"Why?" Haeseul asked, before she could stop herself.

The woman's mouth moved. It was not quite a smile. "Because I wanted to hear your voice, I think."

A warm and wholly unprofessional heat rose in Haeseul's face. She opened her mouth to say something sensible, and behind her, in the second aisle, something went wrong.

Not a sound. It was the absence of one. The refrigerator's hum cut out in the middle of a breath, and the tick of the wall clock stopped, and the whole shop dropped into a silence so total that Haeseul heard her own pulse in her ears. The lights dimmed to a dull, yellow, underwater glow.

At the front door, a man had come in.

She had not heard the bell. He was simply there, a small, stooped man in a padded coat, standing just inside the threshold with his hands hanging at his sides. She knew him. Mr. Gu, who lived two streets down, who came in every Thursday for his blood pressure tablets and always asked after her mother as though she were still alive, because he had forgotten, and Haeseul had never found it in herself to correct him. He was seventy-nine. He had a habit of buttoning his coat all the way to the chin and of humming something tuneless while he waited.

He was not humming now. His eyes were open and fixed on a point somewhere beyond the glass, and his face was slack, wet, utterly unguarded. Tears were running down his cheeks and he did not appear to know it.

"Mr. Gu?" Haeseul said.

He did not move.

Behind her, she heard Gyeol make a thin, frightened sound, and the stranger at the counter said, very quietly, "Do not touch him yet."

But Haeseul was already moving. She did not decide to. Her body simply went, because it had gone toward the frightened and the failing for so many years that it no longer waited for her permission. She crossed the floor, and the air near the door was cold, truly cold, a cold that seemed to lean on her skin with a weight of its own, and she felt something at the edge of her sight, a thickening, a blurring, like breath on a pane of glass. She did not look at it. She looked at Mr. Gu.

"Mr. Gu," she said. "It is Haeseul, from the pharmacy. Can you hear me?"

His lips shaped a word. It might have been a name.

"Your hand is so cold," she said, and she took it between both of hers, not hurriedly, the way she had taken a thousand hands in a thousand hospital rooms. It was papery and chill and trembling. "Come and sit with me. We will warm it. There is a chair just here, you know it, you always sit there. I have your tablets ready."

He turned his face toward her slowly. His eyes were full of a place she could not see. She recognized the look, and the recognition went through her like a blade, because she had worn that look herself, in a gray corridor, in the small hours, when the machines beeped and the clock did not move.

"She is calling me," he whispered. "Hyeon-sook. She is calling and I cannot find the room."

"I know," Haeseul said gently. "I know. It is hard to find a room in the dark. But you are not in the dark, Mr. Gu. You are in the pharmacy, and it is very late, and I am right here. Do you feel my hands? Squeeze them. That is right. Tell me what you can feel."

"Your hands."

"Good. And what else?"

"The floor." His breath hitched. "My shoes are wet."

"It is raining a little outside," she said, which was untrue, but it was the right kind of untrue, an ordinary, solid thing for him to stand on. "You walked in the rain to see me, you foolish man. Come and sit."

She led him, one small step at a time, across the cold floor to the chair beside the counter, where the old people sat while they waited. She sat him down and knelt in front of him and kept hold of his hands. She talked. She did not know what she said. She said the names of the streets he lived on, and the name of the tea shop at the bottom of the hill, and the weather, and the colour of the tablets he took, and as she talked she felt the strange, thick cold draw back from them by degrees, not all at once, but as a tide leaves a beach, reluctantly, still holding on to the sand.

The silence loosened. A hum started up, and it was only the refrigerator. The clock resumed its tick. The yellow light lifted, and the fluorescent white came flooding back, and Mr. Gu blinked, and his eyes cleared, and he looked at her with sudden, bewildered, ordinary kindness.

"Ah," he said. "Pharmacist Yeon. Have I come at a bad time?"

"Not at all," said Haeseul, and her voice shook only a little. "You are right on time. Shall I make you some tea?"

"I would not want to trouble you."

"It is no trouble."

She stood on legs that did not feel quite like hers. Gyeol had crept up from the second aisle and was hovering a few steps away, as pale as paper, holding the paper cup he had never drunk from. She gave him a look that meant, plainly, fetch the kettle, and he fled to the back room with the air of a person escaping a burning building. Haeseul turned to retrieve the old man's tablets, and found herself face to face with the stranger.

The woman had not left the counter. She was standing exactly where she had been, the paper cup still in both hands, but she had moved closer without Haeseul noticing, and she was looking at Haeseul with an expression Haeseul could not file under anything she knew. There was astonishment in it, certainly. There was something like awe. And underneath both, a kind of fierce, unwilling hunger, like a person who has just seen water after days in a desert and is trying to behave as though she is not thirsty.

"How did you do that?" the woman said, very softly.

"Do what?" Haeseul asked. "He was having an episode. It happens, with the elderly. I have had practice."

"You walked into it."

"Into what?"

The woman's eyes searched her face. For a moment Haeseul thought she would answer. Her lips parted, and her fingers tightened on the cup, and something enormous and unspoken pressed up behind her teeth.

Then she said, "You are not afraid."

It was not a question. It sounded, if anything, like a verdict, or a prayer. And Haeseul, who had been steady for twenty minutes, who had been steady for years, felt the floor of herself tilt very slightly.

"Of what?" she said. "Of an old man who was sad?"

The woman gave a short, soft breath that was almost a laugh. "Yes," she said. "Of that."

"I am afraid of plenty of things," Haeseul said, with more honesty than she intended. "I am afraid of the electricity bill. I am afraid of the fish market on Mondays. But I have never been afraid of someone who was hurting."

The woman looked at her for one more long moment. Then she set the cup down on the counter with great care, as though it were made of something that could break. Her fingers were still not quite steady.

"I have taken enough of your time," she said.

"You have not bought anything."

"No." The woman turned toward the door. At the threshold, with one hand on the glass, she paused, and Haeseul saw her shoulders rise and fall once, a breath drawn in and held. "Thank you for the water," she said, without turning around. "It was the first thing anyone has given me in a long while that I did not have to carry."

Then the bell rang its one bright note, and the door swung, and the night closed over her.

Haeseul stood there with her hands open at her sides. After a moment she became aware that she was gripping the edge of the counter. She let go. She flexed her fingers. Her heart was going hard and fast, with no good reason, and she put one hand flat against her breastbone and told it, silently and sternly, to stop.

It did not stop. She stood in the white humming light and wondered why it felt as though a door had opened somewhere she had not known there was a wall.

Mr. Gu drank his tea in the old chair by the counter, with Gyeol hovering beside him and apologizing for the temperature of the water. By four o'clock he was himself again, talking about his tomato plants and the price of anchovies, and when Haeseul put the paper bag of tablets into his hands, he squeezed her fingers and told her she was a good girl and that her mother must be proud. She said, "Thank you, Mr. Gu," and she did not correct him, and she walked him to the door and watched him go down the slope under the streetlamps, a small padded shape growing smaller, until the curve of the hill took him.

"Noona," Gyeol said behind her. His voice was thin. "Noona, I do not think that was a normal episode."

"It was an episode," she said.

"The lights went yellow."

"The wiring is old."

"The clock stopped."

"Gyeol." She turned, and she was very gentle, because he looked as though he might cry. "You are tired. I am tired. It was a strange hour and a strange night, and tomorrow we will both be sensible. Go and wash your face. Then you are going to eat something. That is an order from your senior."

He looked at her for a long moment. She knew that look. It was the look of a person deciding whether to believe what they were told or what they had seen. Finally he nodded, and went, and she heard the tap run in the back room.

Haeseul stood alone in the middle of the shop.

The lights were steady. The refrigerator hummed. The clock on the wall ticked on, patient and ordinary, and she looked at it, and for no reason she could name she thought of the woman's hands, the dark tips of the fingers, the trembling pressed flat against the doorframe. Oil, she thought. Fine machine oil. The kind a person got on their hands from working with small brass parts.

She went behind the counter and opened the green notebook again. Her pen hovered over the page. She wrote nothing. After a time she closed it, and slid it back under the register, and turned the silver ring once around her finger, and then again, and then again.

It was only when she went to wipe the counter, a task she had already done twice that night, that she noticed what had been left there.

It lay beside the paper cup, small and flat and slightly curled at the corners, the way a card gets when it has been carried in a pocket for a very long time. She picked it up. It was old, heavy stock, the color of weak tea. Printed on one side in faded black letters were two words and a small drawing of a clock face with no hands.

SLOW HOURS.

Below the words, in an address she did not know and a handwriting so neat it might have been engraved, was a street name in the old harbor quarter. And on the back, in the same precise hand, written in pencil so light she had to tilt it toward the lamp to read, was a single line.

Before the new moon.

Haeseul turned the card over once, and then again. Outside, the wind moved among the signboards. Somewhere down the hill, a ship's horn sounded, long and low, like a breath let out after being held for years.

She did not throw the card away. She told herself she would, in a moment, as soon as she had finished wiping the counter. But when the sky began to pale over the harbor and Gyeol had gone home and the morning crowd was no more than a rumor of footsteps in the street, she was still standing there, and the card was in the pocket of her cardigan, warm from her hand, and she could not have said when she had put it there.