Twenty minutes later she was back, dripping and shivering.

“I forgot to bring a towel,” she said.

“I didn’t.” Finn handed her a thin white sheet.

“You went after Caroline with a towel?”

“I didn’t go after Caroline at all. I just came down here to do some writing, and I sort of thought you might be along later, so I brought a towel just in case.”

“How did you know?”

“Message from Third Cubicle Jesus.” Finn turned round and stared at the car park while Ava peeled off her wet underwear and put on her jeans and jumper.

“I must be freezing but I can’t feel it,” Ava said. “I can only tell because my fingers won’t work properly. If I don’t go back soon, Paul’s probably going to leave too. Why aren’t I going back?”

“Because you’re not sure if you care,” said Finn. “I’m sorry, but it’s true. You don’t know if you really like him, or if you just feel like you ought to.”

“Damn it,” said Ava, and sat down on the sand. After a minute, Finn began writing with his stick again.

“What are you doing?” Ava asked.

“It’s a story,” said Finn. “A story for the sea. It’s about a mermaid who tries to live in Birmingham. In the end she realises it won’t work, and goes back to the sea, but it takes a long time. There, it’s finished.” Finn sat down beside her in the sand. “It’ll dry out overnight and blow away by morning. And the sea will take the rest.”

“Why write it on the sand? Why not on paper?”

“Because,” said Finn, and threw away his stick.

“I can’t believe how long it’s been since we came here,” said Ava, gazing regretfully at the glitter of the streetlights reflected in the water.

“Look, the dunes are nearly an island. One day we’ll live there.”

“When we’re old, you mean?”

“Or when everyone’s sick of us laughing about stuff only we think’s funny.” Ava wrapped her arms around herself and shivered. “Are you cold? Have my jacket.”

“Then you’ll be cold. Besides, it’ll never fit.”

“Course it’ll fit, you dimwit.” He wrapped the shabby military jacket around her shoulders. “I could wrap this around you twice if I had to.”

“Do you think,” said Ava, “I completely fucked us both up when we were kids, and now we’ll never be able to sustain proper adult relationships?”

“Don’t be daft.”

“But… ”

“But nothing,” said Finn firmly, and tossed Caroline’s hairclip into the sea.

Chapter Nine: Now

Today might be the last time, or it might not.

Sometimes I see him and I can’t believe it. Not like he’s a movie star or anything. It just seems weird. Like I made it up, or dreamed it. Except if it really was a story or a dream, we’d both be the bad guys.

Until she saw him standing in the shadows, Alicia was convinced in her bones he wouldn’t be there. It would be like when she’d been younger and thought that if her dad would just take her to London she’d definitely, definitely meet Rihanna. Then their train had pulled into Paddington and she’d suddenly understood how very big the world was and how many people there were in it.