Then Farah: her T-shirt drenched in it, her jeans black with it. “What did you do?”

Farah looks up and stares at me like she’s seeing me for the first time. There’s more blood flecking her cheek. She pushes her hand forward, flat on the desk. Among the treacle-streaks of gungy blood I can see that she has seven … no … eight fingers.

“What’s happening?” Chiu whispers.

“It’s Puzzles,” I answer.

“Help me,” Farah gasps.

She grabs her wrist with her free hand. There are more fingers now, nine … no ten … they swell and split, bulging from under the skin and then bursting out, contorted and malformed. I draw an empty breath.

“Cut them,” Farah pleads. “Please cut them.”

“I can’t.”

“It hurts…”

I can hardly bear to look at the hand, the thought of cutting into those twisted, alien fingers makes me sick. But I know what will happen if I don’t. Already her wrist and the lower part of her forearm are beginning to bulge and shift, before long her hand will be gone altogether and then her arm and then … her.

Treat the symptoms.

I have to do what Jonah did for Tongue.

I step forward and pick up the knife. It’s slick with blood from Farah’s own failed attempts at stopping the disease. I clamp my hand over the back of Farah’s, my knife at the ready.

“Are you sure?” I say.

Farah nods.

“Do it, quickly!” Chiu urges.

I press the knife down on to the back of one of the fingers. It writhes and flexes like an animal trying to escape. It reminds me of the time I held the school hamster when I was little. No one could understand why I was so freaked out by it. But I remember thinking about all those fragile organs and liquid beneath the springy skin of its engorged stomach and I remember thinking, just for a moment, that I might squeeze…

It’s the same pliable softness under my knife now. I imagine myself squeezing the hamster of my childhood until its smooth, round stomach split. I turn away.

Farah screams.

When I look again it’s like our hands are islands in a lake of black blood. The severed finger squirms a moment, then stops, then is gone. When I go for the next finger, Farah pulls back instinctively. I hook my elbow over her arm and pin her in place.

The next finger is easier. It feels like slicing through chorizo.

I slice again and again, and the excised fingers curl away and then melt into the black muck that no longer looks like blood, and that drips in slick rivers on to the floor. Farah’s breaths come in torn mouthfuls like she’s struggling to get enough air. I’m terrified she’s going to die. I’m terrified that I’m killing her. But I cut and cut and cut.

Gradually, finally, the new fingers stop appearing. The ones that are already there fall limp like they’re resigned to their fate. I slice them off one by one. Farah’s breathing slows, her head flung back.

I loosen my grip and step back. Farah curls into a protective ball around her hand. I help her to stand, guide her to the sofa. I take a T-shirt that’s draped over the sofa in a parody of a messy teenager’s laundry and wrap it tenderly around her damaged hand.

She doesn’t resist. She sits, stupefied and inert, and when I’m finished she rolls on to her side and falls asleep.

THIRTY-ONE

Puzzles.

We all know what it means. It means Farah is dying. She’s dying here and she’s dying in the ordinary world; after all, each world is just a reflection of the other.

I think of Chiu’s theory. That being here might prevent us from being able to recover in the ordinary world. If he’s right, then nothing the doctors do there will be of any use. It’ll just be one of those things they don’t fully understand. The limits of science. We’re doing everything we can, they’ll tell her parents. She’s not responding to treatment.

Idiopathic organ failure.

They’re just words we use to describe the things we don’t understand.

We need to get her back.

It’s morning, or at least something that approximates the damp grey of a February morning. But Farah isn’t going anywhere. She’s sitting on the same sofa as she was sitting on hours ago, staring numbly at her bandaged hand. Chiu and I sit on the edges of our seats. Waiting. Watching. She looks scared. But worse than that, she looks resigned. Farah, the fighter, looks beaten.

“Farah,” I say, softly. “We need to go and find the machine. It’s our best chance of getting home, getting better.”

She barely responds.

“Farah, please. We can be there in a couple of hours.”

She starts unwrapping the T-shirt we used as a bandage.

“Don’t,” Chiu says. “Leave it.”

But she carries on, unwinding the dark, stained material with trembling fingers. Her hand, beneath the bandage, is misshapen and discoloured. Gnarled bulges rise from the skin like new knuckle bones where I removed the extra fingers. They look like the scarred bulges that appear on trees when a branch has been cut. They look dead.

“It might not mean anything,” Chiu says hopefully. “Tongue was sick for months. Ose said we don’t know.”

“He’s right,” I say. I try not to think about what it would be like to have to hack off Farah’s fingers on a regular basis. “We can handle it. We know what to do now.”

“You don’t understand,” Farah says. She stares at us both with savage, distrustful eyes. “I’m not like you two. We know what happened to Chiu. His body is fine and if we can get him out of this place, he’ll be able to recover just like the doctors say he will. Kyle, you have epilepsy; you do this kind of thing all the time. But me … I got sick because the tumour is back. I’m dying in the ordinary world because my brain is being squashed by a mass of abnormal tissues. Being stuck here is the least of my problems.”

I shake my head. “We don’t know that.”

“I’m not going back just to be sick,” Farah says.

I look at Chiu and his eyes are wide and worried.

“I’m not doing it,” Farah insists. The scary thing is I believe her. “I’m not going back to have surgeries and treatments and then die anyway. I’m not doing that again.”

“Farah,” I say, trying and failing to keep my voice calm. “Listen to me—”

“You can’t change my mind.”

“Just listen. You don’t know this but I used to watch you in class all the time. I’m sorry if that sounds creepy but it’s true. But you were so cool. I used to want to be like you. Then I got to sit with you in swimming lessons and I can’t believe I made such a mess of it. But I was so scared I could hardly breathe around you, let alone talk to you normally. And now … it’s wild but I got another chance. And it’s different because I know you now. I’ve come to bloody London for you! And I’m not scared anymore, do you see?” Farah stares defiantly at me. I’m not getting through. I see flashes of her storming out of the classroom, the bewildered teacher left in her wake. Farah, who won’t let anybody tell her what to do. But I carry on anyway. “But now I know you and I want more. I want to see you in the ordinary world as well. I want to go to the park and have a picnic with you. I want to go to the cinema and watch a crappy movie with you. I need you back in the ordinary world, Farah, where there’s actually stuff to do beyond playing bloody Uno.”