I button up my coat and reluctantly leave the warmth of the bookshop, emerging onto the freezing street. Above my head, multi-coloured Christmas lights criss-cross between buildings, bathing the street in a vivid glow and lending the city centre a festive feel.

It appears that the shops on this particular street are embroiled in a competition of who can display the most elaborately decorated Christmas tree. Ben’s back is to me and when I call his name, he jumps and spins around, surprised.

‘Ben, my name is Detective Inspector Erika Piper. Would you mind answering a few questions?’

The unwavering confidence he displayed when accosting Reuben for his directorial abilities upstairs a short while ago has vanished at the sight of a police badge.

Ben is tall at about six feet, though his features remain almost-childlike. He has a beanie hat pulled tight over his head, though some long curls haven’t managed to be contained and peek out from underneath. He is sporting some questionable facial hair; a poor attempt at a moustache and some patchy sideburns.

‘Uh, yeah. Am I under arrest?’ he asks, nervously.

I almost smile at his greenness.

‘No. I’d just like to find out a little more about what you were saying upstairs. Shall we sit?’

I motion to a nearby bench and wait for him to take a few steps before following him.

‘Now, talk me thorough why you had such a go at Reuben and Jay?’ I say when we are both perched on the cold metal.

‘Well, I love The Threat books so much that when I heard they were going to turn them into a film, I got so excited. I’d read those books as a young teenager so they left an imprint, you know? But when Blood Ice, shit name by the way, came out, it was so bad. I was so disappointed. He – Reuben,’ he elaborates, noticing my quizzical expression, ‘got it so wrong. He missed out key points from the book and fucked up the things he left in. Anna’s death scene was a pivotal moment in the book, but played such a minor scene in the film. The fact he got her naked for it, too, ruined the whole thing.’

‘He said that wasn’t his decision.’

‘He’s the fucking director, of course it’s his decision,’ he snorts.

‘If you had been the director, would you have done her death scene differently?’

His eyes light up and when he speaks it’s with wild enthusiasm. ‘I would have been true to the book. I’ve read the book, and that chapter in particular so many times I know the scene inside out.’

This extremism alarms me. Why is he so hung up on this particular section of the book?

‘Do you know how Anna died? In real life, I mean.’

‘Yeah,’ he nods, ‘I heard on the radio that the killer recreated the scene from the film. Bet he did a better job than Reuben.’ My eyes widen. ‘Sorry,’ he says, ‘I know that’s a weird thing to say but as a film student, I’ve fantasised about re-doing that scene, properly, to do it justice.’