“Doesn’t it just. But the coroner’s report was inconclusive, there were no witnesses, and he was very drunk. It’s hard to pursue a murder case with no evidence of an actual crime and no suspect. Certainly, DDI Colthorne didn’t want me to. And when he was telling me so, he asked me if we’d found Marks’s ‘papers’. But I had only said his notebooks were missing.”

Joel curled his mug against himself. “So what are you thinking? Marks kept working on the Beech case, found something in the last few months that would look bad for Colthorne...blackmailed him? Is that where the money came from?”

“It’s a theory.”

“Not one that’s very flattering to Mr. Marks.”

“He was a drunk, he needed money, and his clients had left the country,” Aaron said. “Or, more charitably, perhaps he suspected that Colthorne would be able to quash any investigation, so this seemed the only retribution available.”

“And then Colthorne kills him instead. Having got him drunk first?”

“I retraced Marks’ steps to a pub. The barman recalled him buying several doubles and thinks he was sitting with someone, but he couldn’t come up with a description beyond a middle-aged man.”

Joel scowled in thought. “So would Colthorne kill Marks himself or have one of his gang friends do it?”

“I should do it myself, in his shoes.”

“Then he searches Marks’ office for any papers pertaining to himself, or Sammy Beech, or both, and...doesn’t find them? Or finds them and takes them?”

“They’re gone, so someone’s taken them.”

“But if Colthorne had them, why would he need to go to these lengths against you? Or any lengths at all, really? Surely he’d just need to burn the evidence.”

“I can only conclude he thinks I know a lot more than I do. Which is absurd, because if I had Marks’s evidence, I’d have taken it to Scotland Yard or the Home Office already.”

“But he thinks you could get it,” Joel pressed. “He must do, because he’s trying to force you out one way or another. Destroying your reputation via me, or making your life miserable. So can’t we try to find whatever Marks had? Because if you got hold of the evidence he’s murdered at least one person and framed another, I don’t think him spluttering accusations about your friend the queer graphologist would hold much water.”

Aaron reached over and kissed the top of his head. It was the kind of casually affectionate gesture anyone might make, except this was Aaron, and Joel’s whole heart hurt at it. He made himself glower anyway. “Was that an ‘aren’t-you-sweet’ kiss?”

“Perhaps a little,” Aaron said. “I entirely agree that finding Marks’s papers is vital. It’s the finding that’s the hard bit, in part because Davis, the DI, has been running me off my feet.”