I try not to think about the way he led us to the old man’s house. You smell that? It’s not like he had to search door to door, is it?

But I don’t mention it to Chiu and Farah. There’s no point, so why worry them? We’ll keep going, we’ll get to UCL and then … I don’t know.

When Chiu first told us about the machine I thought he was kidding himself. But now, somehow, I’m pinning all my hopes on it too.

The knife I used to kill Tongue is still in my back pocket. It presses uncomfortably against my backside as I walk but I keep it there anyway. I like feeling it close.

We come to a T-junction and Farah consults the map, then starts to the left.

I stop. “Wait.”

Farah gives me a worried look. “What is it?”

I shake my head. My body thrums suddenly with a sense of dread I don’t understand.

“Jonah?”

“No.”

“Then what?”

“I don’t know.”

Farah and Chiu exchange a look.

“We need to keep moving,” Farah says.

I shake my head again. I look down the street to the left. It has a high wall on one side where it borders the train line and a huge block of red-brick flats on the other. The trees that line the road are stark rods of grey wood, cut back and bare.

“We can go right instead, can’t we?” I say, my voice trembling.

Farah glances at her map, shakes her head. “We need to get past the train line. It’s like … an extra three miles that way and then three miles back. It makes no sense.”

I can’t explain. But I know. That way is death, death and more death. Nothing more. I don’t know how I know, but I do.

Farah stares at me, scared and irritable at the same time.

“What is it?” Chiu says.

“I don’t know.”

Farah’s irritation comes out now. “You need to do better than that.”

She glances at Chiu like she’s expecting him to back her up, but he remains silent. I look at the road curving away from us again. It’s like the aura I get before a fit, the certainty that something terrible is coming.

“Jonah could still be behind us,” says Farah. “I’m not walking six miles out of our way because you’re scared of the bloody trees.”

The trees are terrifying now that she mentions it. They look like people who have been strung up to die and hung there so long there’s nothing left but bleached white bones. But it’s the big, blank windows in the red-brick apartments that really scare me. There’s someone waiting for us in that darkness. I don’t know if he’s seen us yet but if we go that way he will and we won’t stand a chance.

Farah glances at Chiu and then back at me.

“I think we should go Kyle’s way,” Chiu says at last.

“What?”

Chiu looks unapologetic. “Kyle’s getting good at this sort of thing.”

We walk more quickly now, our earlier good spirits lessened. Farah strides ahead, her strong, long legs pounding across the pavement. She’s angry at me. Chiu falls into step at my side.

“I’m sorry,” I say, uselessly.

Chiu shrugs. “Blindsight?”

“Maybe. I don’t know.”

“Any other … feelings?”

That we’re walking into something terrible. That we may have avoided immediate death but we won’t avoid it for long.

I shake my head.

It’s all residential houses here, big leafy trees and grand brick properties. One house we pass has actual battlements and I want to point them out to Farah but I figure she’s not in the mood. Right next to it, there’s a modern, six-storey apartment block and across from that, the heavy grey complex of a council estate. I remember reading somewhere that the reason you get so many different styles of houses in London is because of the Second World War. The bombs plucked entire rows of terraces – and entire families – out of the universe and London’s planners have been desperately trying to fill in the gaps ever since.

I like the effect it’s created. I like the way each street has the capacity to hold a secret. A strikingly modern building with a small lawn on the roof sits next to a dignified-looking semi, next to a vacant plot, next to a pub, next to a shop that sells fishing tackle.

I’m in London, I think. I can’t help the whisper of excitement inside me. The vast, throbbing, layered energy of it all. London has weight, just as the traffic on the A5 had weight. It’s more real, more there than the town I grew up in. London fizzes and crackles across worlds. The constant rush of life and death, the tightly packed minds and hope and love and hate. It bends the walls of the world.

I wonder if that’s why I was always drawn here. Because I understood, intuitively, that London straddled both worlds just as I did.

The streets are still empty though. I catch occasional glimpses of people in the ordinary world: an old man shuffling along on the opposite side of the road and then disappearing behind a tree and never re-emerging; a woman watching me from a living-room window before vanishing in the shifting reflections of the glass. There should be more people, more life. But this world is not life, I think, it’s the absence of life, the before and the after, the realization that all of us have already been dead and will be dead again and the thing we call life is just the briefest spark between eternities of blackness.

And all the time, the dull, featureless dome of the sky watches us.

You’ve been out here too long.

I feel it come on all at once. The disequilibrium of the Stillness.

“I need to stop,” Chiu says, a moment later as we cross another main intersection.

He sits heavily on the ground, his legs crossed, his hands in his lap. He stares numbly at his fingers as if he hardly recognizes them.

“No,” I say, panic rising quickly. “We need to keep moving.”

Chiu shakes his head belligerently. “I’m tired.”

Farah walks back to us. “What’s he doing?”

Chiu rolls on to his side and curls into a foetal ball.