I feel the back of my head. There's no tenderness on the skin, no tell-tale lumps, so I haven't been hit over the head. This means I've been drugged, and with something powerful enough that I wouldn't bat an eyelid while Leah, who was a fit young woman, was slaughtered only inches away from me.

I shut my eyes, fighting off another wave of nausea. When I open them again, I find my gaze returning to Leah's body. The blood on her neck wound has coagulated, and the thick patches on the sheets are also drying. She died some time ago, then, two or three hours at least, probably longer, and for the first time I notice the smell in the room, the vague sour odour of faeces and decay that lingers round the recently dead like a humiliating farewell.

Standing there in the dim, leaden silence, it feels as if I've stepped into the middle of someone else's nightmare.

But I'm wrong. As I crouch down and press the play button, I am about to find out that this is my nightmare. And it's only just beginning.

2

I can hear my heart thumping as I sit on the edge of the bed and wait. For several seconds the screen remains blank before wobbling slightly with interference. Then the film starts.

It opens with a static shot of the room I am now in, taken at roughly chest height and facing towards the top of the bed. The bedside lights are on and it's night. Although the focus is very slightly blurred, like a bad home video, it's easy enough to make out Leah lying spread-eagled on the sheets, very much alive. Her wrists and ankles are tied to each of the small wooden posts at the head and foot of the bed, and she is naked. The expression on her face is one of lust. The sight catches me out. In the few short weeks I've known her, Leah and I had a healthy and enjoyable sex life, but it never involved bondage. I suddenly feel uncomfortable, like some kind of voyeur, unearthing secrets that are best left alone.