The letters had survived four decades in a biscuit tin, which was more than Imogen Wren could say for most of her grandmother's things.

She sat at her worktable in the back room of the archive, gloves on, lamp angled low, and eased the brittle paper apart one fold at a time. Restoration was patient work. It rewarded people who noticed what others rushed past. That was, her therapist once told her, either her greatest strength or the reason she was still single at thirty two. Imogen had never decided which.

Outside, London was doing its usual grey drizzle, the kind of rain that didn't so much fall as hang in the air and wait for you. She liked the archive best on days like this. The hush of it. The smell of old paper and beeswax polish. Nobody expected anything of her here except care, and care was something she had in endless supply, even when other things ran short.

The tin had come from her mother, who had inherited it from Eleanor without ever opening it properly. "Too painful," her mother said, which was the kind of explanation that closed a conversation rather than opened one. Imogen had waited a respectful six months after the funeral before she let herself look.

Most of what she found was unremarkable. Ration books. A rosary. Photographs of people whose names nobody living could confirm anymore. And then, near the bottom, a bundle of letters tied with string gone soft and grey with age.

She read them in order, the way she read everything, patiently, thoroughly, letting the story build itself rather than rushing to the end. Eleanor's handwriting was neat and slanted, the hand of a woman who had been taught penmanship mattered. The letters were addressed to a sister back home, and they were, for the most part, exactly what Imogen expected: homesickness, complaints about the food, a running joke about a landlord who never fixed the heating.

Then she reached the letter postmarked Seoul, 1984, and the story stopped being ordinary.

Tell no one about the ledger, Eleanor had written, tucked between a line about the weather and a line about a friend's wedding, as though it belonged there, as though it were nothing. If it surfaces, deny you ever saw it. Some things are safer forgotten. I should never have looked.

Imogen read it three times. Then she turned the page over, searching for a continuation, a footnote, anything that might explain what a ledger was or why her grandmother, a woman who had spent forty years running a modest bed and breakfast in Yorkshire, would ever have written a sentence like that.

There was nothing. The next letter, dated six weeks later, made no mention of it at all.

She sat with the letter a long time after that, the rain ticking against the window, the lamp humming its low electric hum. She thought about calling her mother, but she already knew how that conversation would go. Her mother did not like to be reminded that Eleanor had a life before she was anyone's grandmother. She thought about calling her sister, who would tell her, not unkindly, to leave well enough alone and get some sleep.

Instead Imogen did what she always did when something troubled her: she went looking for the truth of it, carefully, the way she'd been trained to handle anything fragile.

It took her four days to find the shipping records, three more to find the news clipping about an executive who vanished from a Seoul dock in 1986 and was never found, and one long night to realize that the initials on the clipping's byline, the address of the company involved, and a name scrawled faintly in the margin of Eleanor's final letter, all pointed toward the same six weeks in the same city.

By the time Imogen boarded a flight two weeks later, she had told herself a dozen reasons this was reasonable. A research trip. Professional curiosity. The kind of thing an archivist did when a mystery landed in her lap and refused to leave. She did not tell herself the real reason, which was that for the first time in longer than she wanted to admit, something had made her feel entirely, uncomfortably awake.

Seoul at night looked like a city that never quite finished arguing with itself, glass towers and neon signs pressed close against old stone walls, alleyways that smelled of grilled meat and rain. Imogen's contact, a document recovery specialist recommended by a colleague who owed her a favor, had agreed to meet her at a small cafe near Insadong. She arrived ten minutes early, out of habit more than eagerness, and found he was already there.

Jin ho Baek did not look up when she approached the table. He was studying something on a cracked tablet screen, sleeves pushed to his elbows, an expression of complete and slightly unnerving focus, the kind of stillness that made her wonder if he'd noticed her at all.

"You're early," he said, before she'd said a word.

"You're earlier."

That got his attention. He looked up, and for a moment neither of them spoke. His eyes were dark and steady in a way that made her feel, absurdly, like she'd been caught doing something, though she couldn't have said what.

"Imogen Wren," she said, offering her hand.

"I know who you are." He didn't take it. Instead he slid the tablet toward her, screen angled so she could see. "What I don't know is why you're carrying around a name that got three people killed."

The words landed like cold water down her spine.

"I'm sorry?"

"The ledger you mentioned in your email." He kept his voice low, even, the tone of a man used to delivering bad news without causing a scene. "It's real. It's also the reason a shipping executive disappeared in 1986 and was never found. If you have information about it, you should consider very carefully who else knows you have it."

Imogen's mouth had gone dry. She thought of the letter, tucked safely in a folder in her hotel room, and felt suddenly, foolishly exposed, as though she'd carried something radioactive across an ocean without knowing it.

"I found one letter. A single line. I don't even know what the ledger is."

"Then we have that in common." He closed the tablet and stood, dropping bills on the table for a coffee he hadn't touched. "Walk with me. Not here. It isn't safe to talk about this somewhere with fixed cameras."

She should have asked more questions. She should have, at the very least, hesitated the way any sensible person would, weighed the risk, called someone, told a friend where she was and who she was meeting.

Instead she found herself following him out into the crowded street, into the neon and the noise and the smell of rain on hot pavement, aware of exactly one thing with a clarity that unsettled her more than the warning had. Whatever her grandmother had buried in Seoul forty years ago, it was not as buried as everyone had assumed.

And neither, it seemed, watching the careful, guarded way Jin ho moved through the crowd like a man used to being followed, was he.

They walked in silence for several minutes, Jin ho choosing turns that seemed random but weren't, doubling back once through a covered market before cutting down a narrow lane strung with paper lanterns. Imogen kept pace, saying nothing, cataloguing him the way she catalogued everything: the set of his shoulders, the way his eyes moved to shop windows and side mirrors rather than to her, the small scar above his left eyebrow that he'd probably forgotten was even there.

"You're not going to ask why I know so much about a case from before either of us was born," he said finally, without turning his head.

"I assumed you'd tell me if you wanted to."

That, at last, earned her something close to a smile, there and gone so fast she might have imagined it.

"My grandfather worked the docks in Incheon," he said. "He testified once, informally, about cargo that didn't match its manifests. Two weeks later he stopped talking about it. Six months after that, he stopped talking about most things." He glanced at her sideways. "So you understand why a British woman showing up asking about a ledger from 1986 is the kind of thing that keeps me up at night."

Imogen absorbed that in silence, feeling the shape of the evening shift beneath her, the casual research trip she'd told herself this was becoming something with roots and weight and consequence.

"I'm not trying to open old wounds," she said. "I only want to understand what happened to my grandmother."

"Wanting to understand and being allowed to are different things here." He stopped walking, finally, in the mouth of a quiet alley lit by a single string of bulbs. "I'll help you. Not because it's safe, and not because I think it will end well. Because if I don't, you'll keep digging without me, and that will end worse."

"That's a very comforting yes."

"It's the only kind I have."

For the first time since she'd landed, Imogen laughed, short and surprised, and something in his expression eased fractionally, as though he hadn't expected that either.

"Nine days," he said. "That's how long I can give you before I have other obligations. If we haven't found what you need by then, you go home, and you let it go."

"And if we do find it?"

Jin ho was quiet for a moment, and when he answered, his voice had dropped to something quieter, more careful, as though he were admitting a truth he hadn't planned to say aloud.

"Then we'll both have to live with what it costs."

Somewhere behind them, a shutter rattled down over a shop front, too loud in the narrow lane, and Imogen felt her pulse jump before she'd even turned to look. Jin ho's hand found her elbow, light but immovable, steering her deeper into the shadow of the alley without a word of explanation, and in that single unthinking gesture she understood, with a clarity that frightened her more than anything Eleanor had written, that she had just placed her trust in a man she'd known for less than twenty minutes.

It would not be the last time she did.