“Worth contacting army bases in the city…?”

“Do we know who the underworld would go to if they needed firearms…?”

“Are we treating the shooting as an assassination? If it was a pro, they could be ex-army themselves…”

“Except a pro wouldn’t just chuck the weapon, would they? They’d break it up, dispose of it in bits and pieces…”

“Could the gun have belonged to the victim…?”

“Any further tests we could run…?”

After listening, arms folded, for a few minutes, Clarke broke the meeting up, handing out fresh chores to those who needed them. Then she went in search of Fox, and found him in an adjoining room, going through boxes of folders.

“What’s all this?” she asked.

“The Summerhall files,” he explained. “They arrived this morning with the Solicitor General’s blessing.”

“And?”

“And this.” He had found what he was looking for. He placed the relevant documents on the nearest desk. “It was when you mentioned the Falklands.”

Clarke peered at the report. It was dated October 1982 and concerned an army veteran who had been making too much noise late at night in his council flat. Neighbors had complained and—not for the first time—police officers had arrived to deal with the disturbance. The officers had found a small amount of cannabis and, lying on the coffee table in full view, a Browning pistol.

Clarke stopped and looked at Fox. Fox nodded and gestured for her to read on. The ex-soldier’s name was Laurie Martin. He was eventually charged with possession of drugs, but let off with a caution and the advice that he should enter a course of counseling.

“Don’t suppose anyone had heard of posttraumatic stress back then,” Fox commented.

“Am I missing something?” Clarke had turned the sheet over, but it was blank. “The gun didn’t make it onto the charge sheet.”

“No,” Fox said.

“How come?”

He offered only a shrug. “Coincidence?” he suggested.

“You obviously don’t think so. A pistol—same make and probable vintage as the one used to kill Billy Saunders…” She was shaking her head slowly.

“Should we bring Stefan Gilmour back in?”

“What’s the point? I don’t see his name here.” Clarke scanned the report again. “This is all there is? No record of the weapon going into an evidence locker? No mention of it in the courtroom?”

“I could try doing a bit more digging—courts will have their own records…”

“Sounds like another haystack to me.” She had taken out her phone and was finding a number on it.

“Let me guess,” Malcolm Fox said.

Rebus was seated in his car on Great King Street when he got the call.

“Hiya, Siobhan,” he said.

“Where are you?”

“The car park at Gayfield Square,” he lied. “Trying to work up the energy for an hour or two of DCI Page’s company.”

“Have you heard we found the weapon?”