Joe walked out of town along the river. Time travellers tailed him as far as Lammas Land, then lingered at the boundary, dwindling into the distance behind him. In three days’ time, he would graduate, and they would vanish, the last relic of a future that was no longer his. To be honest, he was looking forward to it.

He walked on through the quiet streets of Newnham, out onto the rolling green fields that led down to the water. The grass was studded with groups of third-years, exulting and despairing, futures temporarily on hold. The cloak-and-dagger flag of the Assassins fluttered in the early evening breeze. He spotted Efua among the crowd, but she was the only one he recognised, and being introduced as Backwards Boy would only invite awkward questions. Instead, he went to sit alone by the riverbank, feeling strangely suspended, as if life was happening somewhere else and he was on a train waiting to get there.

His phone vibrated. Rob always got lost on the way to Grantchester. He was preparing to typeLITERALLY JUST FOLLOW THE RIVERwhen he saw the message was from Esi.

His heart seized. Could a Nokia 3210 breach the barrier between universes? It didn’t seem likely. Hands trembling, he opened the message.

:-G

He frowned, tilting his phone.

What is that?

my disappointed face

because you’re not here to meet me

Emotions warred inside him: excitement that she was here, dread that she would soon be gone again. He tried to keep his reply casual.

I wish I’d never taught you about emoticons.

?:-/

that’s you

Why does my hair look like that?

you tell me

where are you?

Grantchester Meadows. Follow the river south. If you see cows, you’re on the right track.

ok

there soon

He turned to face the path. It would take her at least half an hour to walk here, but he didn’t want to miss a single second.

He felt her coming before he saw her. She was wearing a bright red summer dress that lit her up like a conflagration. Her hair was loose and full, framing her face in spiralling curls. He gazed at her like she was the sun and he had spent three days in a darkened room.

She stopped, then turned: she was looking for him. He got to his feet and waved her over. The smile that lit her face when she saw him was a wonder and a heartbreak all at once. He wanted to go to her, take her in his arms and kiss her. But he couldn’t see past the knowledge that this was only temporary: soon, she would be leaving, going back where he couldn’t follow. “So you talked to your family?”

She nodded. “I thought everything would’ve fallen apart without me. But honestly, they were fine.” Her smile returned, deepened. “It was so good to see them. I talked to my dad. Like, really talked. I think he finally gets why I had to come here. And my sisters—I told them about Mum. What she’s really like. Not just the idea they grew up with.”

He couldn’t help smiling back. “That’s brilliant. I’m happy for you.”

“Sorry it took me so long. I figured I should give them some time to adjust to the news.”

He didn’t understand. “What news?”

She lifted the bag he hadn’t noticed hanging off her shoulder. “That I’m moving here.”

His heart cracked with joy. But his brain wouldn’t let him believe it. “I thought you were going to do what Vera does. Live in your universe and just—come and visit me sometimes.”

Her eyes were soft. “I don’t want to be a visitor in your life, Joe. I want to be part of it. And I can still see my family. Every week, if I want to. They’re only a wormhole and a train ride away.” She held up her arm, showing him a tiny scar on the inside of her wrist. “Vera gave me an access chip, so I can always get back.”

He shook his head, the last tendrils of doubt dissolving. “You don’t have to do this for me.”