‘Twenty-eight thousand undergrads, eleven thousand graduate students. Most of them won’t be there today, though. Classes ended last week.’

I spend a minute calculating odds. With that many people, it would be unusual if there wasn’t a disappearance and an assault within the last few months. Probably not relevant to my case. But I stir the information into the batter anyway.

‘Vasquez seemed kind of tense,’ I say.

‘No doubt,’ Thistle says. ‘He’s on the Warner task force.’

Uh oh. ‘The what?’

‘It’s an organised crime case. Only a small group of agents are working it, because they’re worried about corruption. So the workload is huge, and Vasquez is still supposed to manage incoming communications for other cases.’

The FBI is investigating Warner again. Maybe I should try to get close to Vasquez, find out what the group knows. Or maybe I should stay as far away from him as possible.

‘You’re not on the task force?’ I ask.

‘I wasn’t invited,’ Thistle says.

She has suddenly become very intent on the surrounding traffic, deliberately discouraging further questions.

‘I need to know that you can be professional,’ she says finally.

I look at her. She keeps her eyes on the road.

‘You know I can,’ I say.

‘I mean it. If working with me is going to make you uncomfortable, I don’t want your help.’

I need to be on this case so I can sabotage it. Thistle is resourceful. Without my interference, she might follow Biggs’s trail all the way to my freezer.

‘You need me,’ I say.

‘I don’t, actually. I was solving cases just fine until you turned up. I’ve been solving them fine since you left, too.’

‘Your boss thinks you could use my help.’

Thistle’s nose twitches. ‘She doesn’t know you like I do.’

‘What do you mean by that?’ That fear again: She knows.

‘You “solved” our last case by accidentally wandering into the killer’s house,’ Thistle says. ‘If I hadn’t identified him with actual detective work, you’d be dead. I signed an NDA, so I can’t tell my boss about that. But if I could, she might not be so keen on your help.’

‘Maybe,’ I concede.

She says nothing. If I can’t mollify her, she might find some way to kick me off the case, or start working it when I’m not around.

‘Look,’ I say, ‘I get why you don’t want me here. I was an asshole.’

‘Yup.’

‘I’ll work this case with you, and then I’ll disappear. Next time the director asks for my help, I’ll tell her I’m unavailable. What do you say?’

Thistle spins the wheel, taking the Crown Vic into one of the campus parking lots. She glances down at my mutilated hand. A thin smile.

‘I give that plan two thumbs up,’ she says.

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