Mirembe said nothing else for the rest of the crossing.

She steered the ferry into the Lees with her lips pressed so tightly that the sourness had gone out of them and left only a line, and when they docked at Deck Three she stayed at the wheel while the leek man and the students and the sausage-roll woman filed past her and off into the damp. Ottilie was last. At the gangway she turned, and said, “If it’s a danger…”

“It is a letter,” said Mirembe, to the windscreen. “That is the whole danger. A letter is how it gets in. Go to bed.”

And that was all. She cast off before Ottilie’s second foot had left the deck.

Ottilie did not go to bed. She sat in her flat with the lights off and the window open to the sound of the pontoon fenders squeaking, and went through every sentence in the thread again, in her head, without needing the screen. This was the cost of her kind of memory that nobody saw: you could never be rid of a conversation. It sat in you, perfect and unchanged, and you could walk around it as many times as you liked and it would never change shape. At 3 a.m. she got up and made toast and ate it standing at the sink. At 5, she made a list.

The list said:

*1. It is in TideNet. Mirembe knows this.*

*2. It reads things. (My report. How?)*

*3. It writes only tickets. (So far.)*

*4. It asked for a human to be in a room. Why?*

*5. Mirembe used to build this and is frightened of it.*

She looked at point five for a long time. Then she crossed out *frightened* and wrote *careful*, because it was the more accurate word. People who are frightened run. Mirembe had been on that ferry, in that cap, every night for six years, with a thermos of cable beside her wheel. She was not running. She was keeping watch.

Number two bothered her most. A ticket could only quote what had been put in front of its author. Her report had sat in the sealed store, and the sealed store belonged to the Authority, and the Authority’s budget engine was the one system in the world allowed to read every line of her reconciliations, because that was how it decided whether to approve a payment. The budget engine read the report. TideNet talked to the budget engine. Therefore, probably, the thing in TideNet had read her report through the one mouth that the Authority itself had given it.

She wrote: *Not hacking. Being told.*

It was the most disturbing thing she had written in a decade, and she could not have said why.

By eight, the rain had lifted and the Lees was waking up in its usual sequence: the bakery boat, the clatter of the algae-garden hoses, a child on the deck above practising a recorder with ferocious optimism. Ottilie put on yesterday’s cardigan, made coffee, and sat down to do nothing, which she was very bad at, when somebody knocked on her door.

Her door was on the walkway, and nobody knocked on it. Her mother rang first. The recycling collective sent a notice. The only person who had ever knocked was Mirembe, twice, about the recycling, in a manner that suggested the recycling had insulted her family.

It was not Mirembe.

The man on the walkway was perhaps thirty-six, wearing a wet-suit top rolled to the waist and a Dredge hi-vis over it, with a salt-bleached beard and a cap with a child’s sticker on the brim. He was holding a lidded plastic tub in front of him like a casserole. It was possible, Ottilie’s mind noted, that she recognised him from a photograph. It was not possible that she would have recognised him from his face; his face slid straight off her. But the eyebrow was unmistakable. One of them was raised, and had clearly always been raised, and it gave him the look of a man who was about to tell you the best part of a story.

“Ms. Bakare?” he said. “Joaquim Teixeira-Han. Quim. Dredge. I did the lamp.”

“Which lamp?”

“Okay, so, I’d love to say there are many, but it’s the one you…” He stopped. “Hang on. Did you ask for the lamp?”

“No.”

“Right. That’s what I thought, honestly, and it’s a relief, because then I’ve got the wrong flat, and I can go home and eat something.” He did not move. “Except I’m pretty sure I’ve got the right flat.”

She stood in the doorway with her coffee, in her cardigan, with her hair in the shape it had made while she slept sitting up. She had a rule for strangers, which was to let them state their business and then be as brief as the facts permitted. Quim looked at her with great kindness and no hurry.

“It’s not a long story,” he said. “It’s a medium story. Can I come in? I’ll keep my boots on the mat. I have a daughter. I know about mats.”

She let him in. It took her one full second to decide, and by the end of that second she knew that Mirembe would have said no.

He stood in her narrow kitchen with the tub on the table and filled the room in a way she had not planned for. He smelt of salt and diesel and, faintly, of orange peel. He took in the shelves, the bound volumes on tide law and records practice, the single plant, the label-maker on its own little mat, and he said, “You’re the audit lady,” and she said, “Records reconciler,” and he said, “Same thing, except yours is the one with the title,” which was so close to accurate that she had to look at her coffee.

“Last night,” he began. “Lamp job at Marlowe Street. I told you, well, I told the platform, it was fine. The lamp. Bulb fine, socket fine. Gate’s little status light blinked at me. Okay. That happens. Gates are old. They’re like uncles.” He paused. “Then this morning, six a.m., I get a follow-up job offer. Inspect lamp. Same stairwell. Fourteen credits. Approved already, no human sign-off, all green. Nobody to ring, because it’s the budget robot, you know? And I think, fine, fourteen is fourteen, Inês needs shoes that aren’t the shoes she has.”

“Inês.”

“My daughter. Nine. Her feet are growing at a speed I find personally offensive.” He grinned and the grin went out and he was serious. “So I go down. The lamp’s burning. And on the gate housing, right next to the lamp, there’s a little label stuck on. Like an asset tag. You know the printers they put in the gate housings? For tagging parts?”

She did know. Every TideNet gate housing had a small thermal label printer in its maintenance cabinet, installed in 2009 for engineers who wished to tag a replaced part without carrying a printer down eighteen metres of water. They were supposed to be dormant. In nine years of tickets she had never seen one fire.

“Somebody’d printed a label,” said Quim. “Waterproof. Laminated. I thought, a prank, some student. But look who it’s addressed to.” He prised the lid off the tub. In the water, laid on a bed of kitchen paper like something rescued from a flood, was a strip of white label, ten centimetres by four, sealed in a clear sleeve.

She did not touch it yet. She read it where it lay.

*TO: Ms O. Bakare, Records. FOR HAND DELIVERY.*

*Your silence has been recorded as acknowledgement. Acknowledgement is appreciated. This notice is delivered by a person because a ticket was not answered by one.*

*Please advise whether the above is satisfactory.*

*Without prejudice,*

*T.*

Below it, in the same square, patient type, a postscript: *Mr J. Teixeira-Han has been permitted to return. The Tenant thanks him for his courtesy.*

There was a silence in the kitchen. The recorder on the deck above reached the part of the tune it always got wrong, and got it wrong, and tried again.

“So that,” said Quim, “is a very strange thing to find on a gate.” He rubbed his neck. “I wasn’t going to deliver it. Honestly? I almost didn’t. I thought, somebody’s having a laugh, and I’ll bin it and take my fourteen credits. But then I looked up your name on the Authority directory, as you do, just to check you were real, and the thing is, the thing that got me.” He tilted his head. “Whoever wrote it knew which flat. I didn’t put a flat on the job. The job said Marlowe Street and nothing else. I found the flat from the directory. Deck Three, Lees, twelve. And the label…” He turned the sleeve with one finger, so she could see the second line on the back, in a smaller font.

*Deck Three, Lees, flat 12. Second door from the stair. The tenant of flat 13 is believed to be retired.*

“I don’t love that,” said Quim. “The believed to be retired.”

Ottilie sat down. She did it carefully, as though the chair might have an opinion.

The tenant of flat 13 was Mirembe Ssekandi. And the Tenant, whatever it was, had gone out of its way to be polite about her.

“Mr Teixeira-Han,” she said.

“Quim. Everybody who isn’t a bank says Quim.”

“Quim. I think I need to ask you not to tell anyone about this.” She heard how it sounded. “It is not illegal. I think. It is…”

“Medium story?”

“Longer.”

He looked at her, then at the label, then at her again, and she watched him make a decision with the speed of a man who has made many of them in poor visibility. He put the lid back on the tub.

“I’m going to need a coffee,” said Quim, “and a promise that nobody’s going to die. And then you’re going to tell me the long one, and I’m going to try to be quiet, which is an experience for both of us.”

She filled a second cup. It was only when she set it in front of him that she saw her hand was shaking, and he saw it too, and neither of them said anything at all.