‘Exactly. Alan was delighted to have the watch fall into his hands, because he knew the McAuleys would pay handsomely for the evidence it contained. This next part is guesswork, but I’m ruling out Alan as Rebecca’s killer, because Marcelo told me he was too soft, and because otherwise he would have destroyed the photos instead of selling them. And because he’s selling them, I figure that thirty-five years is long enough and Alan has burned enough bridges that he figures it’s no longer worth protecting whoever he was protecting back then.’

I took a second to see if most of the room agreed this was reasonable. Some were nodding along. Sofia looked like she was about to vomit. Andy looked befuddled, as if I were explaining quantum physics. Good enough.

‘But Alan’s got a problem. He might not have killed Rebecca, but he’s not innocent: he was working for the Sabres. He targeted Robert and helped hide Rebecca’s body, at the very least, and it’s likely he interfered with the ransom drop too. So he can’t just show up on the McAuleys’ doorstep. They’d hold him just as responsible. So he needs a middleman.’

‘Why Michael?’ Katherine asked.

‘It took me a while to figure this out. I think that Alan wanted someone else with something to gain, to be sure that he could trust them to deliver such a large amount of money. A Cunningham had plenty to gain from the photographs, and from what else Alan knew from his involvement. The most obvious is learning the truth about Robert, of course. I suspect that’s only half of it, but we’re getting there. Michael seems like the right choice – Marcelo, you were Robert’s lawyer; Katherine, you’re straight as an ice skate; Audrey, your age puts the odds against you here, no offence. But this was Alan’s mistake. The personal connection he thought would guarantee the deal turned out to be the reason Michael killed him.

‘And the deal itself is the simple part. Alan’s price tag is the original ransom amount: three hundred thousand dollars. So Alan gives Michael enough information to rope him and the McAuleys in, Michael gets the money from the McAuleys to buy the microdot from Alan, Alan gives him a cut, and then Michael delivers the photographs back. It’s all so simple. Except, of course, Michael ends up killing Alan and keeping the cash.’

‘Because Michael didn’t have three hundred thousand dollars,’ Sofia slurred, surprising me with her attention. ‘You told me he gave you two sixty-seven.’