She tried to put a finger on why she found it so strange to think of Adrian in that way. Maybe because they were friends first and foremost. Many relationships start with lust and progress to friendship. To be fair, that had never worked out for her. All she knew was that when she was in that shower with Adrian she certainly wasn’t thinking about him as a friend. Thank God he felt the same way. Could she wait? Were they past the point where they could get to know each other? Of course, she knew she still had a lot to learn about Adrian. She blushed at the prospect. Christ, she had to get ready for work and stop getting fired up like this.

At the station, Gary and Adrian ushered Imogen into the liaison room. If their goal was to seem nonchalant, they failed. She shook her head; they couldn’t look more conspicuous if they tried.

‘What is it?’

‘We found something out about the wife, Abigail Lucas. Well, Gary did,’ Adrian said.

‘Go on.’

‘She left the university because she claimed she was assaulted and the university basically didn’t give a shit. Tried to sweep it under the carpet,’ Gary said.

‘Who assaulted her?’ Imogen asked.

‘That’s never mentioned in any of the emails,’ Gary said.

‘And what’s that got to do with this?’

‘In the emails to Coley, Lassiter suggests using it as leverage to get her involved in some kind of programme, but I think it’s more of a game,’ Gary said.

‘Game?’

‘Yeah, as soon as I saw that it all clicked into place. I saw a movie like it once, a French movie, fucking horrible it was,’ Gary said.

‘OK, so how does it work?’

‘You start by getting a person you can control somewhat, either financially or with some secret they might have that they don’t want to go public. In the movie, it was about winning a large sum of money, but I don’t think that’s what’s happening here. Then you get them to do things they wouldn’t normally do, immoral or illegal things, and escalate it until they are doing some properly messed-up stuff. Once you get people involved in the game, it becomes harder for them to leave when they have committed any of the acts. You get them on the hook, then when you have them there you threaten them with exposure in order to compel them to commit another slightly more heinous act.’

‘How far does it go?’

‘As far as they want. Who can say? There is a possibility the other killer we are looking for is one of the others, like Caitlin. That maybe the killings were part of the challenges being set. Or maybe they just pushed someone too far and they lost the plot.’

‘Why am I surprised by anything that people do?’ Imogen said wearily.

‘Caitlin claimed she didn’t know any of the other people involved, only Gillian Mitchell, who was the one who was controlling her,’ Adrian said.