Arch seventeen. The water feels particularly deep and cold here. I shiver and want to fold my arms around myself but I need to keep them out at my sides, so I don’t fall. I have my own choice to make: whether I let Mum back into my life or not. I see her face, how it was in the café, when she looked at me. How so much was written there, while so much remained unsaid. I need to really think about that look. I need to wonder how she felt when she came to look for Angela and me, and Cherry Lau told her we weren’t there. When she was finally ready for us, but it was too late. Do I want it to be too late for my mother and me? That’s what I need to decide.

I’m at arch twenty.

‘Can you still hear me?’ comes a distant call, faint and ghostly, from the end of the tunnel I am far from now.

‘Not really,’ I shout, at the top of my voice, as I trudge through unseen water.

‘We’ll say goodbye for now.’ At least I think that’s what the distant voice says. The words sound dreamlike, melancholy. Goodbye. It’s never goodbye with us, Dad, is it? It’s, Mind how you go.

‘Just for now, Pops!’ I whisper. I won’t be long, Dad. I promise I won’t be long.

It is silent now, bar the occasional drip of moisture from brick to shallows and the steady beating of my own heart. The slurp of my lower legs in soaked denim through dark water. I’m on my own. What if I can’t get the hatch open? What if no one hears my cries? What if I get help but it’s too late?

Kemp. I haven’t dared think about what he said to me earlier, but now, here in the dark, in this cathedral-like chamber, I hear him again. His words … ‘You’re home to me … I look at her and I think, Yeah, her.’ I can see the look in his eyes when he said those words to me, on the streets of London, in bright sunlight. How he smiled. How I could see the whole universe in those eyes, if I chose to.