“We’ve searched his home and looked into whether he had a safe deposit box or kept anything at his bank. He didn’t.”

“Who did he talk to? Friends, family? Does anyone know what he was working on?”

“Not that we’ve yet found. He was a loner, and kept his business confidential.”

The DDI leaned back and steepled his hands. “Look, Fowler, I can see why you wanted to look twice at this, quite apart from pot-hunting.”

“From what, sir?”

“Oh, don’t be coy. We all like to have our picture in the newspapers, and once you have a taste of fame, it’s very tempting to pursue more. Well, you have quite the publicity-hungry family, don’t you?”

“Sir—”

“But the Met isn’t here to bolster your public profile,” Colthorne said over his objection, “and we don’t need your egoism getting in the way of your job.”

The injustice of that was a slap. Aaron inhaled involuntarily to protest, met Colthorne’s eyes, saw nothing but mild amusement.

Behind the mask there’s a sodding great void where a person should be.

“You can’t make up a murder from lost keys,” Colthorne went on. “By the way, I knew Marks slightly. Were you aware of that, Fowler?”

It was a simple question, simply asked. It felt menacing all the same, and Aaron had an instinctive urge to deny everything, but that would put Challice in hot water. “I believe so, sir.”

“Mmm. He approached me over an old case, one where the guilty man’s family felt justice had not been done. He didn’t make a good impression, I must say. He was all too clearly a drinker, and in my view he was milking the Beech family for what he could get. That conviction was one of the surest of my career and I rather resent the attacks on my character that resulted.”

“Sir.”

“I understand the Beeches have given up their efforts to get him cleared?”

“They’ve emigrated, sir.”

“Good. Good. A new start. I do despise charlatans like Marks who whip up grudges. I don’t suppose any of us would look marvellous if someone set out to dissect every act and motive and mistake of our lives.” His eyes locked with Aaron’s. “Do you, Fowler? Would your character survive close examination—from an uncharitable perspective?”

Aaron’s throat felt thick. “No, sir.”

Colthorne gave it a long few seconds, then clicked his tongue. “Well. Marks met a bad end, and if it was foul play it must be dealt with, but on the face of things, it seems to me that you’ve a bee in your bonnet. From now on you will report directly to me regarding any further lines of enquiry on the Marks case, and I will tell you if I think your theories have merit.”

He sounded so reasonable. Aaron said, “Sir.”