The thing was, I didn’t know what she was capable of. Large parts of Charlie’s life, her past, were still shrouded in secrecy. I shook my head, was tempted to screw up the paper, rip it to shreds. Was I the crazy one, entertaining these possibilities? I forced myself to carry on, to write down the last suspected crime.

Me pushed down steps.

Why would she do this? If she loved me, why would she want to hurt me? The answer came quickly:

To keep you trapped in your flat. To stop you starting your job. To make you her prisoner, like a pet in a cage.

Was that her idea of love?

I got up, paced the room, feeling light-headed and nauseated, then returned to the list, trying to view these possible crimes coolly, rationally.

All of them had a logical explanation that didn’t involve Charlie. She definitely hadn’t been there the day I’d fallen down the steps. Did that mean she had enlisted someone else’s help? The more I studied the list, the more my head hurt. Perhaps I should go to the police, let them gather the evidence . . . No, I couldn’t. I didn’t want to risk her leaving me before I knew for certain. But if I distrusted her enough to suspect her of any of this, could I really love her as much as I claimed? Yes, yes I could.

Another little voice in my head whispered: And if she is guilty – would you forgive her? Would you want to be with her anyway? Maybe it excites you, turns you on?

I shook my head violently.

It came down to this: I loved her. I wanted her to be innocent but I didn’t know if she was. I needed more proof before I went to the police or confronted her. And if, as I prayed, she was innocent, I could clear my head of all this and we could go on as before. But she could never know I had suspected her. I had to be discreet.

I walked across the room, thinking about secrets stacked upon secrets, and as I reached the window, something crashed into the glass.

‘Jesus!’ I cried out. What the hell was that?

I looked down. A small bird – a sparrow or starling – lay dead on the tiny balcony. I rubbed my arms and heard Karen’s neighbour’s voice in my head. A dark spirit has attached itself to you. I shivered. It was getting dark outside, the streetlights flicking on. I stared at the dead bird, with its broken neck and mashed beak, and realised I needed to retrieve it so it didn’t rot and start to stink.

I pushed the sash window up and went to look for a carrier bag. As I was hunting beneath the sink, where dozens of plastic bags lived inside other plastic bags, the doorbell rang.

I pressed the intercom. ‘Hello?’