I asked if she’d ever actually heard any voices, but she said no – it was much more like a feeling. ‘I wish I’d heard voices,’ she said. ‘It would have made the whole thing easier to explain. Of course now I realise it was a telepathic compulsion.’

I was afraid to ask from who – but I had to know.

‘From aliens,’ she told me.

‘Aliens?’

‘I’m not mad, you know,’ she said. ‘I’ve been sectioned. They kept me in for four weeks’ “evaluation” and at the end the top shrink calls me into her office and looks me in the eye and says, “You’re saner than I am – go away”.’

‘Did you tell them about the aliens?’ I asked.

‘I may have glossed over some of the details,’ she said, and dunked a biscuit.

Definitely sane, I thought.

‘So would it be fair to say that you were summoned out that night?’

I didn’t ask whether the summoner had been an invisible unicorn – that would have been leading the witness. You learn about this stuff when you do your PEACE (Planning, Engage and explain, Account & clarify, Closure, Evaluate) training – the not leading the witness bit, not the unicorn. They’re one of the things you have to pick up on the job.

‘Not exactly,’ she said and gave me a rueful smile. ‘I walked in on my dad shagging my babysitter.’

‘No shit,’ I said, and then realised who that must have been. ‘Joanne Marstowe?’

‘The very bitch,’ said Zoe. ‘They didn’t see me, of course – too busy – so I went upstairs, packed my things and went out the front door. I slammed it hard, too, but they must have been too busy to even hear that.’

‘Wait,’ I said, doing the maths in my head. ‘She must have had Hannah by then – where was she?’

Zoe shrugged.

‘I don’t know,’ she said. ‘Not at our house.’

And I’d seen enough of the Derek and Joanne Show to know that they were probably still at it eleven years later. It was outrageous, but I wasn’t sure it was relevant – I was certainly not going to write it up this time. To change the subject, I pulled up a picture on my phone of the knapsack they’d found near the B4362 during the search and showed it to Zoe.

‘Was this yours?’

‘Oh my god,’ Zoe grabbed my phone and brought it right up to her face. ‘That’s my bag. I got it free with a magazine – I loved that bag.’

I explained where and when it had been found.

‘I’m amazed it lasted that long.’

‘So you had it with you when you left the house?’