‘Josh Billingham?’ She nods. ‘Does he live in Exeter too?’ She nods again. ‘That should do it. Ariel does it on her phone. It’s like magic. You just put in someone’s name and it brings up everything about them. Their favourite photos and everything. It’s weird.’

‘I’m glad you got on my train, sweetie.’

‘Me too.’

‘I wonder how they’ll get you back to your shopping mall in time. The universe, or whoever it is that does it. Something will happen.’

As she says that the ticket inspector appears. I look at Lara.

‘One adult and one child to London, please,’ she says.

‘How old is he?’ says the ticket guy. Oldish, grumpy.

‘Fifteen,’ I say.

‘Any ID?’ he says.

‘Nope.’

‘Convenient for you to be the oldest possible child age,’ he says.

‘You got me,’ I say. ‘I’m thirty-five.’

He rolls his eyes, huffs and gives me a child ticket. Lara pays for them both. We look at each other.

‘What if I do make it, though?’ I say. ‘What then?’

At some point around Reading I look at my mobile phone. There are a million calls from Dad, and school, and Troy and Gus. I don’t listen to the answerphone messages. I switch the phone off and put it away. They can’t get me like that. I talk to Lara. She tells me about how she came to realize that she was reliving the same day.

‘God knows how many times I did it before I worked it out,’ she says. ‘Though I could hazard a guess now that you say it’s 2019 out there. It started as a sense of déjà vu, and then I realized that it wasn’t that I felt like it had happened before: it was because it completely had happened before. Everything came gradually into focus, and then, when you piece it all together, it’s devastating, isn’t it? So we don’t have long before we get to London. Listen to this bit: there’s a guy in Cornwall. Leo. I decided to get up earlier and catch a train in the wrong direction once. I was so sure it would work, and it did for a bit, but the train broke down at Bodmin Parkway and I ended up on the fast train to Paddington. Anyway, there was a lovely old-fashioned station cafe at Bodmin, and I got a cup of tea just for the comfort of something warm to hold. There was a guy in there dancing around and being weird, and after a while we realized we were the same.’

‘How did you know?’

‘The same way I did about you. You did about me. The blue thing that you only see when you start looking for it. The blue light that shines out of someone.’ She looks at me, questioning. ‘At least that’s what I see.’

‘Yeah. Me too. Ariel does as well.’