"First rule," said Sefa, as they went down the iron ladder, "you don't touch anything."

"I never touch anything."

"Second rule. If I tell you to run, you run, and you don't bargain about where."

"That's a rule I could do with some terms on."

"Third rule." She dropped the last three rungs and landed with a grunt. "You tell me the minute you see anyone you know. Anyone. I don't care if it's the baker. I'm told by the only reliable source I have, which is myself, that you'll insist on coming. So you're coming. But you will do it my way."

Pico considered this with his head on one side, gravely. "Can I be called Deputy?"

"No."

"Assistant Chief?"

"Pico."

"Fine." He kicked a stone. "It's still a very good job."

They went by the back ways. That was the first thing the note had taught her, and she was almost ashamed of how quickly she took it up: no phone, no map, no clever route on the screen. The town's one mobile mast stood on the guild's roof and the guild's cables ran under its streets, and nothing in Tuzlag that travelled by signal was private from the people who owned the signal. She had known that all her life as one knows that the tap in the yard is cold. She had never before had a reason to feel it.

Her phone, switched to flight mode, sat at the bottom of her coat pocket like a stone.

Tuzlag was waking up around them. Shutters rattled up. Women in headscarves went by with trays of flat bread. A tabby cat sat on a satellite dish, regarding a pigeon. From a first-floor window somebody's alarm was playing an old pop song, tinny and off-key, and somebody else was shouting at it. The salt-rakers had gone out in a long file to the pans and the first heat was beginning to lift off the roofs, shimmering.

"Where are we going?" Sefa said, because she did not know, and it was a humiliating thing to say.

"Past the cold store. Behind. Where they dump the old buses."

"There's a bus dump?"

"Chief Forger, you took me there the first time. You said it was the only place in town where nobody looked." He glanced up at her sideways. "That's a joke, actually. You said that. I'm quoting."

"I'm not in the mood for my own jokes."

"Nobody ever is," said Pico, wisely.

Behind the Tuzlag cold store, where the lane ran out into a heap of cracked pallets and broken crates, a rusting wire fence enclosed an acre of what had once been the Sebkha Transit depot. Six buses stood in it. They had stopped running the winter the river did, when the line to Karabel was closed, and for eleven years the wind had been carrying salt against them in long white drifts, so that each bus stood up to its axles in its own little dune. The paint had gone, in places, to the colour of old teeth. A goat was asleep on the roof of the first.

Pico went straight to the fifth.

It was the biggest, a long coach with a drooping nose and its number on the side, in blistered stencil: 9. It had been green once, or blue; it was hard to say. Sefa stood looking at it for a long time with her hand over her mouth.

"What?" said Pico.

"Nothing. I was trying to remember if I'd ever seen it."

"Have you?"

"I think I've seen a hundred like it." She dropped the hand. "Where's the lock?"

He showed her. It was not on the door at all but on the rear emergency hatch, a rusted square panel with a scrap of chain across it and a small, shining, expensive padlock that looked as though it had wandered in from another life. Pico fished the key from his sock. His hand shook a little. The padlock opened on the first try.

"That's a Concord lock," he whispered. "They don't pick. They count."

"They what?"

"They count how many times you got it wrong."

Inside, the bus was dim and hot and smelled of old vinyl and dust and, very faintly, of something sharper: a clean, mineral bite in the nose, the smell of a place where someone had been grinding a cough-sweet. Light fell through the dusty windows in long yellow stripes. The seats were torn. The driver's wheel had been taken out. And in the third row from the back, under a seat on the left-hand side, someone had screwed a small sheet of tin to the underside of the frame, so cleverly that you would have had to lie on the floor to see it.

Sefa lay on the floor.

There was a catch. It turned stiffly. The sheet swung down, and behind it, held in a bracket, was a biscuit tin.

It was the sort of tin you find in every grandmother's cupboard. On the lid was a faded painting of a rosy-faced child holding a basket of apples. Underneath, in permanent marker, someone had written in her own long slanting hand: *SORRY ABOUT THIS.*

She took it out and sat up with her back against the seat, and Pico, to his credit, sat down opposite without a word and folded his hands.

The lid came off with a sound like an exhaled breath.

Inside were nine small twists of waxed paper. Each was about the size of a pea, each sealed with a spot of red wax, and each labelled on a tiny slip of masking tape in the same handwriting. She picked up the first, and the slip, in her own printed capitals, said:

*MAMA'S LULLABY (3 BARS ONLY). LOST AT 19. FIRST WRIT.*

Her fingers went numb.

She did not remember a lullaby. She remembered, certainly, that she had a mother, that her name was Anwen, and that she had died when Sefa was seven. She remembered Bunmi's kitchen, and the funeral, and the smell of the candles. She remembered, if she tried, a pair of hands plaiting her hair. But she had no song. Where there should have been a song there was a smooth place, like a stone worn flat by a river, and she realised she had walked round it for seven years and never once put her foot in it.

She put the twist down very gently and picked up the next.

*DR AGOSTI'S WAITING ROOM. THE FISH TANK. 20.*

The next. *FIRST SNOW IN KARABEL, 21. I WAS HAPPY.*

*THE SMELL OF THE SHOP BEFORE IT WAS THE SHOP.*

*BUNMI LAUGHING SO HARD SHE HAD TO SIT ON THE FLOOR. (PICO'S FIRST CHRISTMAS?)*

"That's me," said Pico, softly. He had come round the edge of the tin to read upside down. "That's the fish soup. That was real. That was actually funny."

"You weren't there," she said. "I was by myself. I don't remember it at all."

"I was there. You weren't by yourself." His voice had gone strange. "You laughed so much you couldn't talk. And Bunmi got the hiccups."

She didn't have an answer. She went on turning the twists in her palm. Each of them was a day she had lived and lost and, in some past hour of foresight and misery, scraped from her own arm in the dark and labelled so that she would at least have the name of what had been taken. Some of them she had written like jokes, because that was the only way she could stand to. Some had a few words only. She read down the row of tiny slips, and a long, slow cold began to climb her back.

The ninth twist was the last and the smallest. It was wrapped in blue paper instead of white and sealed twice. Its label was not in capitals. It was written as neatly as a legal notice, in the small upright script she used for contracts.

*THE NIGHT BUNMI TOLD ME THE TRUTH ABOUT MAMA. DO NOT BREATHE THIS ALONE.*

She held the little blue pea of paper on her palm and was aware, quite suddenly, that the bus was very quiet.

"Sefa?" said Pico.

There was no rule in the world, she thought, that said you had to know what you'd forgotten. There was no law that required you to be told that a woman who raised you had once sat you down and handed you the truth about your own mother, and that you'd cried, and nodded, and understood, and then written a writ, and that all of it was now a flat stone, under a tin, with a warning.

Bunmi had never said a word.

In seven years, in twenty-six, in every kitchen and every quarrel and every long night on the Quay, the old woman had looked her in the face and had not said that the truth had ever been told.