Halcott & Boye occupied the third and fourth floors of a narrow Georgian building on Fetter Lane, sandwiched between a coffee shop that charged too much and a print firm that had been there since before the street was pedestrianised. The building had no lift. The carpets on the staircase were burgundy and slightly worn at the centre, and the whole place smelled faintly of paper and central heating and the particular kind of ambition that came with billing by the hour.
Zara was back at her desk by noon.
Mr. Adeyemi had not asked questions when she returned. He had simply slid a new file toward her side of the shared workspace and gone back to his phone call. She appreciated that about him. He was not unkind, but he was efficient, and efficiency in this building meant not wasting words on things that weren't billable.
She opened the file.
She stared at it for four minutes without reading a single word.
Then she closed it, opened a fresh document, and started typing.
She titled it Personal Notes — LO. Not a case file. Not a formal document. Just a record. The kind of thing she had trained herself to do during lectures when the information was coming too fast — write it down before the shape of it slipped away.
She typed what she knew.
Lena Obi. Twentytwo years old. Communications student. Attended a party at the residence of Ethan Mears, Greenwich, on the evening of the eighth. Entered the building at 11:47 p.m. Ethan Mears exited alone at 2:14 a.m. Corridor camera offline from 1:52 to 2:31 a.m. Lena found deceased at 7:05 a.m. Single gunshot wound. No weapon recovered at scene. No registered firearm in Ethan Mears's name.
She read it back.
Then she typed the question that had been sitting at the back of her mind since the tube ride home.
Who turned the camera off?
Because that was the thing. Security cameras in a building like that didn't simply go dark. They were on managed systems — monitored, backed up, maintained by a contracted service. A camera going offline meant either a technical fault or a deliberate interruption. And a technical fault that lasted exactly thirty nine minutes and resolved itself cleanly before the lobby camera picked up Ethan crossing the floor felt less like coincidence and more like planning.
She underlined the word planning.
Planning meant premeditation. Premeditation meant the argument — whatever it had been, however it had started — was not the reason Lena was dead. It was the occasion.
Zara sat back in her chair and looked at the ceiling for a moment.
She was not a detective. She had told herself that twice already today and it had not slowed her down either time.
She found Ethan Mears's public profile without much effort. He wasn't hard to locate. He had a website for his studio — a clean, minimal page in dark grey and white called Mears Interactive — and a professional profile that listed two completed titles and one in development. The completed titles were both first person shooters. The one in development was called Clearance Protocol. The banner image showed a figure in tactical gear holding a compact sidearm.
She clicked through to the game's development page.
There was a blog section. He updated it sporadically — patch notes, design decisions, the occasional post about mechanics. She read through several of them. He wrote the way he had seemed in person: precise, economical, not interested in small talk. One post from three months ago was titled Getting the Ballistics Right. It was detailed. He had researched ammunition types, recoil patterns, sound profiles. He had consulted online forums where people who knew firearms discussed them with the kind of fluency that came from real familiarity.
The pistol modelled in the game was a compact nine millimetre.
Zara wrote that down.
She did not know yet what caliber the bullet recovered from the scene was. That information had not been shared with her — she had no right to it, officially. But Detective Ola had not denied her observation when she raised it at the scene. He had simply gone careful. And careful, in her experience, meant she was close to something.
She needed that detail confirmed.
She thought about how to get it.
She called Detective Ola at half past two. He picked up on the third ring.
"Ms. Ademi."
"I told you I'd go home," she said. "I went home. Then I came back to work. I'm not at the scene."
A pause. She thought she heard something close to amusement in it, though she wasn't certain.
"What can I do for you?"
"I want to ask you something and I want you to tell me honestly if I'm in the right area."
"I can't share details of an active investigation."
"I'm not asking for details. I'm asking for a direction. If I'm wrong, just say nothing and I'll move on."
Another pause. Longer this time.
"Go ahead," he said.
"The bullet recovered from the scene," she said. "Nine millimetre."
Silence.
Not a denial. Not a correction.
She let it sit for three seconds.
"Thank you," she said, and ended the call.
She sat very still for a moment after that.
A nine millimetre compact. No registered weapon. A game built around the same caliber, researched in forensic detail by the man who built it. A victim who had been his girlfriend. A camera that went dark at exactly the right time.
It was circumstantial. All of it. Every piece.
She knew enough about law to know that circumstantial evidence built cases every single day — and she knew enough about reality to know it also failed them just as often. What she had was a shape. A silhouette. The kind of thing that told you something was there without telling you exactly what it was.
She needed the weapon.
And the weapon was gone.
She pulled up a map on her screen. Ethan's building in Greenwich. The Thames, running wide and grey two streets to the north. She measured the distance with her eye — close enough that on a clear night, standing on his roof terrace, you could probably hear the water.
She typed consumer drones range and payload capacity into the search bar and spent twenty minutes reading.
Most midrange consumer drones could carry between two hundred grams and one kilogram. A compact ninemillimetre pistol — unloaded — weighed somewhere in the region of six hundred grams. Easily within range. The Thames at 2 a.m. was dark and largely unobserved. A drone flying low, with its indicator lights disabled, would be nearly invisible.
She typed Thames tidal patterns Greenwich next.
The tide. That was the other thing. If the weapon had been dropped into the river, the tidal movement would have carried it. The Thames at Greenwich was tidal — the water moved both ways depending on the cycle. If she could establish what the tide was doing between 1:52 and 2:14 on the morning of the ninth, she might be able to narrow the recovery area.
She found a tide table. She found the data for the ninth.
Low tide at Greenwich had been at 3:41 a.m. The water at 2 a.m. would have been on the ebb — moving east, toward the estuary.
East. Toward Woolwich. Toward the deeper, faster water past the barrier.
She wrote all of it down.
Then she sat back and looked at what she had.
It was not nothing. It was not enough. But it was more than thirty-nine minutes of silence, which was all she'd had this morning.
She left the office at six and took the overground to Greenwich.
She told herself she was only going to look. She was not going to approach the building, not going to speak to anyone connected to the case, not going to do anything that a second year law intern with no formal standing had any business doing.
She stood on the riverside path north of the building and looked at the water.
The Thames at evening was a different thing from the Thames in photographs. It was wide and brown and it moved with a quiet, indifferent authority that made the city on either bank feel temporary. Joggers passed her. A couple walked a dog. Somewhere upstream a barge was moving slowly against the current, its low engine a steady hum under everything else.
She looked east.
Somewhere out there, in the silt and the cold and the dark, was the thing that turned this from a case that couldn't be proven into one that could.
She looked at the building. At the rooftop terrace visible above the sixth floor parapet. At the single light on in a high corner unit that she had no way of confirming was his.
She took out her phone and added a new line to her notes.
Drone launch point: rooftop or terrace. Direction: north toward river. Payload dropped on ebb tide, 2 a.m. approx. Current carrying east. Recovery zone: Woolwich Reach or beyond.
Talk to someone who knows the river.
She put the phone away and walked back to the station.
The call came at 9 p.m., when she was at the kitchen table helping her younger brother Kofi with a geography worksheet and trying not to think about the fact that the scan deposit was due in four days.
It was a number she didn't recognise.
She stepped into the hallway and answered.
"Ms. Ademi." It was Ola again. His voice had a different texture now — still controlled, but underneath it something that hadn't been there this afternoon. "Where are you?"
"Home," she said. "Why?"
"We had a development this evening. Ethan Mears came into the station voluntarily. With a solicitor."
She waited.
"He's changing his account of the evening. He's now saying there was an argument. That things escalated. That Lena had a weapon — that it was hers, that she brought it to the apartment — and that he acted in selfdefence."
The hallway was quiet. Through the kitchen door she could hear Kofi asking something about river systems and her mother's voice answering him gently.
"He's building a defence," she said.
"He's building something," Ola said. "I thought you should know. Since you seem to be thinking about this already."
"Why are you telling me?"
A pause.
"Because in three hours he went from a grieving boyfriend to a man with a prepared legal position. And the speed of that tells me his solicitor has been ready for this since before this morning."
She understood what he was saying. He wasn't asking her to do anything. He was telling her that the clock had just changed shape.
"The self defence claim only works if the weapon existed," she said. "And if the weapon existed, it needs to have come from somewhere. There'll be a purchase record, a registration, a point of origin. Something."
"Yes," he said.
"And if there isn't one—"
"Then someone is going to have to find a way to explain that," he said. "Either side."
She leaned against the hallway wall. Thought about the tide tables. About Woolwich Reach. About a drone flying north in the dark above the river.
"I'll be in touch," she said.
She went back to the kitchen. Sat down next to Kofi. Helped him label a diagram of a river's lower course — the wide, slow
part where the water carried everything it had picked up along the way and deposited it, eventually, at the mouth.
Deposition, the worksheet called it.
She circled the word without meaning to.