‘You do,’ Lara says. ‘And I need an Ariel of my own. Shit. You know, I never thought to try to find someone from the future to help. It’s weird, yes? Because we’re living outside of time. Your Ariel is in 2019. Which must mean that in some way it’s 2019 now, but we can only live in 1999?’ She stares down at her knitting. ‘Is this baby nearly twenty? Fuck. I’m going to need a bigger jumper. Or is time different? Is it no year at all? And have you two just collided for whatever reason?’ She looks at me with narrowed eyes. ‘Do you fancy each other? Is it that? A love story outside of space and time?’

I laugh. ‘Lara,’ I say, ‘of course I fancy her.’

I stop and listen to what I’ve just said. It sounds so straightforward and I know that it’s true. I haven’t properly admitted it until now.

‘She’s beautiful, and funny, and alive, and until I met you I thought she was my only friend in the universe.’

‘Can you …? OK, pretend this doesn’t sound creepy. Can you touch her?’

‘No!’ I laugh because finally someone understands. I laugh because otherwise I’d cry. ‘That’s how we found out. I was pissing her off and she was standing in the doorway and I wanted to leave so I tried to push past. She said it felt really strange for her, when my hand went right through her. Kind of fizzy and cold. I didn’t feel anything, but I don’t quite like to tell her that.’

‘Mmm. That would be annoying for a girl to hear. You make me feel … nothing.’

‘Can I be your boyfriend?’ I say in a stupid voice. ‘I’m dead, and if I was alive I’d be inappropriately old for you, and also when I touch you I feel absolutely nothing.’

We laugh and laugh. I’m annoyed when the train slows down and I realize we’re coming into Paddington. I don’t want to be there, not yet. I’m not ready for Lara to die. I’m not ready to be carted back to Devon, but I know those things are both about to happen.

The police are standing at the ticket barriers.

‘Joseph Simpson?’ says one.

‘No,’ says Lara, stepping in front of me. ‘That’s not his name. This is my son, Kevin.’ I snigger a bit at being called Kevin, then stop because what if this works? What if it actually works? ‘So please leave him alone.’

She’s using a kind of teacher voice now, and she sounds scary. I’d leave me alone if I was them, but that’s maybe why I would never have been in the police.

‘I’m sorry, madam,’ says a woman, who’s very small but hard as nails. ‘We can clear this up quickly. I just need to see his ID.’