I stepped closer to him. ‘I’m talking about what you did to Sasha.’

He stepped back. ‘You know that little bitch?’

‘She’s my best friend. And she’s told me everything – your sordid affair, what you did to her in that hotel room, the threatening texts, the way you set your wife on her. All of it.’

He sneered at me, though his face had turned white. He looked me up and down. ‘What are you doing in here? Did she tell a pack of lies about you too?’

‘What? No. But I know—’

He jabbed a finger at me. ‘I have no reason to explain myself to you, whoever you are. But this girl is a liar. I never had an affair with her. In fact, for your information, I have never, ever been unfaithful to my wife. I certainly never attacked the silly girl.’ He twisted and turned as he spoke, a ball of kinetic energy. ‘I was barely aware of her existence until the police turned up at my office this morning.’

‘Bullshit,’ I said. ‘How can you say that? She works for you.’

‘Hundreds of people work for me. Do you think I know them all?’

I ignored him. ‘And I know you had an affair. She told me all about it. She told me all about your . . . proclivities.’

‘My what?’

‘She told me what you like to do in bed.’

He stared at me, then burst out laughing. ‘Did she indeed?’ He seemed genuinely amused. ‘Tell me, does your friend have mental health issues? We normally screen for that sort of thing, but a few slip through the net. Psychometric tests aren’t foolproof, unfortunately.’

Now it was my turn to be affronted. ‘No, she hasn’t. Is that going to be your defence in court?’

He sat down on the bench, suddenly calm and collected. ‘It will never get to court. Sarah or Sasha or whatever her name is – she’s a liar. A fantasist. She’s invented the whole thing.’

‘I don’t believe you,’ I said.

He shrugged. ‘You know what? I don’t care.’

Before I could say any more, or make sense of this, the door opened and the officer with the baby sick stain beckoned me out.

‘You can make your phone call now.’

He pointed to a pay phone on the wall opposite. I hadn’t used a pay phone in years, was barely aware they still existed. I picked the receiver up and realised I was going to have to pay for the call myself. I fished in my pockets and found two 20p pieces. I pushed one into the slot and dialled Tilly’s mobile number, one of the few phone numbers I knew by heart.

She picked up after four rings, but all I could hear was a great rushing howl. It was like she was standing at the centre of a hurricane, or there was extreme interference on the line.