I remembered him talking about it when we were both in Alderney. ‘It may be a great story,’ I said. ‘But I can’t write about it. I wasn’t there.’

‘I could tell you what happened.’

‘I’m sorry. I’m not interested.’ I reached out for one of the biscuits, then changed my mind. They were somehow unappetising. A chocolate hashtag. ‘Anyway, it’s not just about the crimes, Hawthorne. How can I write about you when I know almost nothing about you?’

‘I’m a detective. What else do you need to know?’

‘We’ve already been into this. I know you’re a very private person. But you’ve got to see things from my point of view. You can’t have a main character who doesn’t give anything away, and frankly, being with you, I feel I’m up against a brick wall.’

‘What do you want to know?’

‘Are you being serious?’

‘Ask me!’

‘All right.’ About twenty questions arrived at the same moment, but I asked the first one that came into my head. ‘What happened at Reeth?’

‘I don’t even know where that is.’

‘When we were in that pub in Yorkshire, a man called Mike Carlyle said that he knew you from Reeth, although he called you Billy.’

‘He’d got the wrong person. That wasn’t me.’

‘And there’s something I didn’t tell you.’ I paused. ‘When I got back from Alderney, a postcard came. It was from Derek Abbott.’

Abbott was the convicted child pornographer we’d met in Alderney. He was the man who’d supposedly fallen down the stairs while he was in police custody.

‘He wrote to you from hell?’ Hawthorne asked.

‘He wrote to me before he died. He told me to ask you about Reeth.’

‘I don’t know anything about Reeth. It’s a place. I haven’t been there.’

I knew he was lying, but there was no point in challenging him. ‘All right, then,’ I said. ‘Tell me about your wife. Your son. What about your brother, the estate agent? How old are you really? You said you were thirty-nine in Alderney, but I think you’re older.’

‘That’s not very nice.’

I ignored him. ‘Why do you make all these models? What’s that all about? Why don’t you ever eat?’

Hawthorne looked uncomfortable. His hand edged towards the cigarette packet and I knew that he wanted to light up. ‘You don’t need any of this,’ he complained. ‘That’s not what the books are about. They’re about murder!’ He made it sound attractive, as if violent death was something to be desired. ‘If you really want to put in stuff about me, why don’t you just make it up?’

‘That’s exactly my point!’ I exclaimed. ‘I prefer making things up. I don’t find it easy writing books when I don’t know the ending. I don’t like walking three steps behind you like the murder-mystery equivalent of the Duke of Edinburgh. I’m sorry, Hawthorne. But this hasn’t been much fun for me. I’ve been stabbed twice! I’ve never come anywhere close to getting anything right. And even if I did want to continue, you haven’t got any more cases for us to investigate together – besides which, I made a mistake with the titles.’