I took a deep breath and created a forma in my mind. It was like Lux, which you use for creating werelights and, with a bit of modification, fireballs, skinny grenades and a really hot flame thing that I have hopes I could use for burning through steel if only I could get the heat to go in one direction only. Like the ESP experiments, I try to avoid telling Nightingale about my little innovations unless I have to explain why one of the labs is on fire. Lux was perfect because it’s known to put a lot of magic into the environment, and what I was going for was cool but noisy.

A dim blue light filled my concrete coffin, which was now half full of water. Reflections rippled across the ceiling in thin twists of green. I tried to maintain it for as long as I could, but the pain in my head got worse and the forma slipped from my mind.

In my imagination, I began to hear the voices of the dead. At least I hoped it was my imagination. A lot of people have died in the Underground, through accidents, through stupidity, or suicide. All the one-unders whose dying wish had been to make other people late for work.

I heard all these one-unders as distant wordless cries of despair and anger that cut off with the same sudden bluntness as Macky the luckless graffiti artist.

‘I’m not one of them,’ I shouted – although I think it was only in my head.

And suddenly they were upon me. All the accumulated casualties, from the train crashes and the fires and the victims of the hideous suicide of the Bradford boy who didn’t want to work in Father’s chip shop no more. A lot of them had gone without warning but others had time to realise what was happening and some, the worst of all the cries, had time to build up a head of hope before the darkness swept them up into the stone and concrete memory of the tunnels.

The rising water was a cold band across my chest.

I didn’t want to die, but the truth is that the choice isn’t in your hands.

Sometimes the only thing you can do is wait, endure and hope.

I heard rattling and scraping above me and for a moment I thought it might be Sir Tyburn back for another chat, but then I heard the unmistakable and beautiful sound of a pneumatic drill.

I waited for a pause in the drilling and gave panicked screaming one last shot – this time with feeling.

Dust filled my mouth.

Then there was light in my eyes which was suddenly obscured by a big black face.

‘You all right, mate?’ asked the face. I refocused and caught a flash of yellow helmet and heavy fire-resistant jacket. ‘Are you Peter Grant?’

I tried to say yes but my throat was clogged with dust.