‘Look, I was a kid. She led me on,’ he said. ‘All over me all night, then I walk her home and suddenly she changes her mind, and I’m supposed to just stop? I didn’t mean to – it was an accident. She shouldn’t have fought so hard, I wasn’t planning to hurt her. Not at first.’

A small pulse was beating in my throat. ‘So you did kill her.’

He shrugged. ‘Accidentally. I was a teenager, for God’s sake.’

‘And Anna? You were with her that night. You did go to the house – you lied to me.’

A sigh. ‘Sam spilled the beans, didn’t he? Colette heard you. I told him not to mention it, but he doesn’t understand, poor kid. Never thought you’d talk to him, to be honest. Unlucky, that.’

So that was why Alex had followed me here. He knew I was on to him. I was very aware of my heart, how it raced in my chest. ‘Colette, she made up the alibi for you?’

He shrugged. ‘Very keen to help me out, poor bereaved single dad that I am. Nice girl.’ He rested his hands on my shoulders. My breath was coming fast, I tried to control it.

‘You told the police I was at Anna’s house the other day – you saw me?’

Again, a soft laugh. ‘That really was dumb of you. Honestly, some of your behaviour – let’s just say it’s been a real gift to me.’

I flinched. The idea that he’d been watching all this time, seeing me stumble about, tangling myself further in his web.

He moved back, sat on my desk. ‘So, you know my story. How about you tell me the truth about yours? Let’s be honest with each other, Casey. At last.’

I felt nineteen again, terrified, lost. ‘I didn’t do it.’

He sighed. ‘That’s not true, though, is it? I read all about it. No one else went into the house or came out. Someone would have seen an intruder – or all the security cameras on that street, they would have captured it, right? And there was no back way in, it was too overgrown.’ He’d looked into it, then. He knew all the arguments against me. ‘So it was you or it was one of the parents,’ he went on. ‘And the police said neither of them could have killed themselves. So what was it, a suicide pact they just happened to act out in the ten minutes you stepped outside with the baby?’ He was sneering at me now.