‘Um, I don’t know him that well. He came to clean the pool and do the garden. Three times a week, but he hadn’t come for a while either.’ Because David hadn’t paid him. I wondered if they knew about that.

‘And was that one of his days, Monday?’

‘Not usually, but sometimes if he wasn’t finished he might stop by again.’ I hadn’t really noticed him, I suppose. People came and went sometimes, dropping off packages, doing Abby’s hair or giving her massages or fixing things around the house. But none of them had keys. The murderer must have had a key, the police insisted. Unless I’d left the door open when I took Carson out. I wished I could remember that moment of stepping out the door. The rush of heat to my head. Flip-flops slapping on hot tarmac. But I hadn’t known how important it would be, to remember every detail of those few minutes.

‘So José could have been there that day.’

‘He could have. But like I said, he hadn’t been for a while.’

It was true, I told myself. For all I knew he’d come back that day. No one would have thought to tell me.

He nodded, and I sensed him warming to me a little. ‘See? This is helpful. That’s all you need to do, Casey – be helpful. This man José, where is he from? Is he documented?’

‘I have no idea. He’s from Colombia, I think.’

José had told me this once, reluctantly, when I tried to make conversation as he cleaned the pool filter. I was so lonely I kept badgering him, but he didn’t want to talk. I found out much later he had wanted his daughter to nanny for the Safrans, since she had a degree in childcare and four years’ experience, but they had preferred an unqualified British girl. A white girl.

‘He’s kind of – not that friendly,’ I said. ‘Doesn’t talk much.’

I felt guilty saying these things, but now that the mean cop was being so much nicer it was like water in the desert.

‘Did he ever have a dispute with Mrs Safran or her husband?’

‘Er . . .’ All I was saying was the truth. It was OK to say the truth, wasn’t it? And let them figure out what had happened. ‘He said they hadn’t paid him last month. I heard him and D-David rowing about it, and José said he was going to tell Ab— Mrs Safran.’

‘And did he?’

‘I don’t know. I only overheard them because it was so loud.’ And because I had opened the bathroom window and stuck my head out to eavesdrop.

‘Interesting. So he might have had a grudge against the family.’

‘I don’t know. I don’t know.’