The rooftop access logs came back on a Thursday.
Zara knew this because Ola called her at 7:48 a.m., while she was standing in the kitchen making Kofi's packed lunch, the bread still in her hand and the phone wedged between her ear and her shoulder.
"The building uses a key fob system," he said, without preamble. "Every entry point logged. Stairwell door to the rooftop terrace registered a fob access at 2:03 a.m. on the ninth."
She set the bread down.
"His fob?"
"Registered to unit 6C. Ethan Mears."
She was quiet for a moment. Through the kitchen window the sky was a flat, uninflected grey, the kind that promised neither rain nor light, just duration.
"So between 1:52, when the corridor camera went offline, and 2:14, when the lobby camera shows him leaving — he went to the roof."
"He went to the roof," Ola confirmed.
"Eleven minutes," she said. "Enough time to launch a drone, cross to the river, drop a payload, and return the drone. Depending on the model."
"We've been looking at his purchase history," Ola said. "Credit card records, subpoenaed this morning. He bought a DJI Mavic three months ago. Payload capacity up to one kilogram. GPS-controlled return-to-home function."
She thought about that. A drone that could fly itself back. You didn't even have to watch it go. You could send it north over the rooftops toward the water, drop what it was carrying, and have it back in your hands before the cold had fully settled into your fingers. Then back downstairs. Through the lobby. Out the front door. Hands visible. Empty.
"The drone itself," she said. "Do you have it?"
"Not yet. His apartment has been under search warrant since yesterday afternoon. No drone recovered on the premises."
"He got rid of it after," she said. "Or it's in storage somewhere. A unit, a locker. Somewhere that isn't his flat."
"We're looking."
"The GPS logs," she said. "If it's a DJI model, the flight data is stored onboard and synced to the manufacturer's app. If he didn't wipe it—"
"We've already contacted DJI's legal team," he said. "Account registered in his name. Flight logs pending disclosure."
She exhaled slowly.
It was building. The kind of accumulation she had watched happen in case files — each individual piece unremarkable in isolation, but placed in sequence they produced something that had weight, that had direction, that pointed at one specific person standing at the centre of it.
"His solicitor is going to move fast once he knows about the flight logs," she said.
"He already knows," Ola said. "We informed Mears this morning. His legal team requested an emergency meeting with the CPS."
"They'll try to suppress the drone data. Or argue the logs are inconclusive without the device itself."
"Probably."
"Don't let them," she said. It came out more direct than she intended.
A pause on the line.
"Ms. Ademi," he said, and there was something careful in the way he said it now, a new register, "I need to ask you something. How much of this have you documented?"
"Everything," she said. "Forum screenshots, tide data, the foreshore contact, the photo from the mudlarker. All timestamped."
"That documentation — it can't be obtained improperly. If any of it is going to be useful to the prosecution—"
"It's all open source," she said. "Public forum, public tide tables, voluntary contact with a private citizen who found an object and reported it through the correct channels. Nothing I accessed required authorisation I didn't have."
Another pause.
"You've thought about this," he said.
"I'm a law intern," she said. "I think about admissibility the way other people think about weather."
This time she was certain she heard something close to a laugh. He covered it quickly.
"I'll be in touch," he said.
She picked the bread back up and finished Kofi's sandwich.
The firm was quiet that morning in the particular way it got quiet when something large was moving through it invisibly. She noticed it as soon as she came in — Mr. Halcott's office door closed when it was usually open by nine, Mr. Adeyemi on the phone with the kind of focused stillness that meant the call mattered.
She sat down and opened her current file. A commercial tenancy dispute in Bermondsey. She worked through it steadily, cleanly, flagging two inconsistencies in the break clause that she wrote up in a revision note by eleven.
At half past eleven, Mr. Adeyemi appeared beside her desk.
"You're doing good work," he said. "The Southwark note was sharp."
"Thank you."
He was quiet for a moment, in the way that meant there was more.
"I heard about your friend," he said. "The young woman in Greenwich."
She looked up at him.
"It was on the news this morning," he said. "They've named a suspect. Formally."
She hadn't seen it yet. She had been on the phone, then on the bus, then at her desk.
"Ethan Mears," she said. It wasn't a question.
He nodded. "They're saying new forensic evidence. A weapon recovered from the Thames."
She kept her expression even.
"Good," she said.
He looked at her for a moment with something she couldn't quite categorise — not pity, not quite admiration either. Something between the two that was more honest than either.
"If you need time—" he started.
"I need the work," she said. "Genuinely."
He nodded once and went back to his desk.
She saw the news coverage at lunch. Sat in the small break room with her phone, reading three separate reports.
The language was careful, as it always was at this stage — a man in his thirties has been arrested in connection with — but the details were specific enough that anyone paying attention could reconstruct the shape of it. The weapon recovered from the Thames. The security camera anomaly. The forensic examination of the apartment.
Ethan's solicitor had released a statement. She read it twice.
Our client maintains that he acted in self-defence following a confrontation initiated by the deceased. We are confident that a full examination of the evidence will support his account. We urge the public to allow the judicial process to proceed without prejudice.
She put the phone face down on the table.
The self-defence claim was still standing. Of course it was. A solicitor prepared well in advance didn't abandon the architecture of a story simply because the walls were showing cracks. They reinforced. They reframed. They waited to see which pieces of evidence the prosecution could actually land in court and built their case around the gaps.
The weapon was recovered. But it was water-damaged, serial number removed, its chain of custody beginning on a foreshore at dawn rather than in a shop or a registered owner's possession. Connecting it to Ethan required the drone. Connecting the drone required the flight logs. And the flight logs required DJI's legal disclosure, which his team would challenge on every procedural ground available to them.
She understood now why Ola had asked about her documentation.
He wasn't just being careful about admissibility. He was telling her that the official channels were going to be slow — that the prosecution's case was solid in shape but still being built in substance — and that anything which could support it mattered.
She went back to her desk.
She opened a new document.
She spent the afternoon building a timeline. Not for herself this time — she had that in her head clearly enough. For someone else. For the file that would eventually go before the Crown Prosecution Service and sit in front of people who needed to see the sequence laid out without ambiguity.
She was careful. She cited only what was sourced. She flagged what was inference and marked it separately from what was documented. She referenced the tide tables by date and source. She included the forum account activity with timestamps. She described the foreshore recovery and attached the photograph she had received, noting that the original had been surrendered to the Thames foreshore authority and subsequently to the Metropolitan Police.
She wrote it the way she wrote revision notes for the firm — clean, precise, no excess. Every claim tethered to something solid.
When she finished she read it back.
It was eleven pages.
She saved it. Then she sent it to her personal email. Then she printed one copy, folded it into an envelope, and addressed it to Detective Ola at Lewisham station.
She had considered calling. But some things were better received in writing. It was harder to set aside something with weight in your hands.
The call she wasn't expecting came at twenty past six, as she was walking to the station.
The number was withheld.
She answered anyway.
The voice was male. Not Ola. Younger, and with the polished flatness of someone who had been trained to sound neutral.
"Am I speaking with Zara Ademi?"
"Who is this?"
"My name is Jordan Fitch. I'm a junior associate at Carver Pennick."
She knew the name. Carver Pennick was a mid-size criminal defence firm. Solid reputation. Not cheap.
"Ethan Mears's firm," she said.
A pause.
"I'm not calling about Mr. Mears directly," the voice said. "I'm calling as a courtesy. To let you know that our client is aware of certain investigative activity conducted by a private individual in connection with this case. And that if that activity has produced materials which are being shared with the prosecution—"
"Stop," she said.
She had stopped walking. She was standing on the pavement, people moving past her on both sides, the evening cold against her face.
"I'm going to say one thing," she said. "Everything I've done has been legal, open-source, and fully documentable. If your client wants to challenge its use in court, he's welcome to do that in court. That's what courts are for."
"Ms. Ademi—"
"And if this call is intended to discourage me from cooperating with the Metropolitan Police investigation into the death of my friend," she said, "then I'd suggest you speak to a senior partner before you call me again. Because that is a conversation that goes somewhere neither of us wants it to go."
Silence.
"Have a good evening," she said, and ended the call.
She stood still for a moment. Her heart was going faster than she would have liked. She breathed through it.
Then she kept walking.
She did not tell Ola about the call that night. She wrote it down — the time, the number listed as withheld, the name Jordan Fitch, the firm, the substance of what was said — and she added it to her document.
If it became relevant, it was recorded.
If it didn't, it cost her nothing.
She was at the kitchen table again by eight, helping Kofi with a science worksheet on forces and motion, when her mother appeared in the doorway in her dressing gown, a cup of tea in both hands, looking at Zara with the particular expression she had — the one that meant she had been watching for longer than she was admitting.
"You're not doing his homework," her mother said. "You're thinking."
"I can do both," Zara said.
Her mother made a sound that was not agreement and sat down at the other end of the table.
"The scan," Zara said, without looking up. "I've covered the deposit. The rest I'll have sorted by the twenty-second."
"I wasn't going to ask."
"I know. I'm telling you anyway."
Her mother was quiet. The kitchen settled around them — the small sounds of the flat, the distant street, Kofi's pencil on paper.
"You were friends with her a long time," her mother said eventually.
"Three years," Zara said.
"I'm sorry, baby."
Zara looked up then. Her mother's face in the kitchen light, tired and warm and entirely familiar.
"I know," she said.
She went back to the worksheet. Kofi had drawn a diagram of a ball rolling down a slope and labelled the forces acting on it in his careful, deliberate handwriting.
Gravity. Friction. Momentum.
She looked at the words.
A body in motion, she thought, stays in motion. And everything that acts against it — every force, every resistance — leaves a mark.
Ethan Mears had tried to make Lena's death look like nothing. Like a gap in a camera feed, a story about self-defence, a gun that had never officially existed.
He had forgotten that the things you put in motion don't disappear. They only change direction.
The river had brought it back.
Tomorrow, she thought, the court would hear it.