Now I knew she felt I was shutting her out and she was hurt. I was going to have to give her something, but I couldn’t tell her the truth. I hit the same barrier every time I thought about confiding in someone. I couldn’t tell Izzy, I couldn’t tell Sasha, and I couldn’t tell Gus or Abby, or Ms Duke or Jasper, because none of them would believe me, and all of them would think I was crazy, and the people in Joe’s family would be horribly hurt.

An empty school is an eerie place. My shoes squeaked along the corridors and up the stairs, and then I was outside the geography rooms, where there were posters of volcanoes and oxbow lakes, and right at the end of the corridor … there he was. There was Joe. He had that blue thing around him right away because I’d looked at a picture of a river just before I saw him.

I ran to him, my arms outstretched. I ran through him, just for fun, and shivered at the sensation. ‘Oh my God!’ I said, laughing.

‘Well, hello, you,’ he said. ‘It worked.’

‘Look at us!’

We couldn’t stop smiling at each other. I didn’t think I’d ever been so pleased to see anyone.

‘What does this mean?’ I was trying to work it out. My phone pinged. I ignored it.

‘It means we’re amazing!’ said Joe. ‘That’s what it means.’

‘Right?’ I did a little dance. No one in 2019 was watching after all. Joe joined in. He grinned and attempted a cartwheel. It was shit, but that didn’t stop him doing another three. I could see him beginning to embrace his world.

‘And it might –’ He stopped abruptly, then started again. ‘It might mean that if we can be in the same place at the same time of day, and if it’s a place that exists in both our worlds, we can meet up and do things. Or it might not,’ he added quickly. ‘I have no idea.’

‘Let’s work out a time and place. See if we can do it. It would be the most …’ I had to stop speaking. It was too much. I checked my phone instead, then grinned and held it out.

‘Hey! Look!’

Ariel. Sorry for short notice AGAIN, but could you babysit for a couple of hours tomorrow, 4 to 6ish? My mum’s going into hospital and I really want to be with her. It would involve picking up the girls from after-school club, because I know you have school yourself so can’t be there at 3.20, and taking them home, just hanging out, and then Gus will be back at 6. I understand short notice & that you’re prob busy. Could’ve asked other babysitter, but girls insist on you!! Abby xxx