“Maybe,” Dervish says, smiling crookedly, looking at his hands with a mix of pride and wonder. “I did most of it without thinking. It was like there was somebody else inside me, pulling the strings.”

“The steel windows were a good idea,” Shark commends him. “You’re more imaginative than me. I’d have tried to drag the demon back.”

“How long will the window to the other universe remain open?” Dervish asks.

“Maybe a few minutes,” Shark says. “We’ll stick by it until it closes, to be safe, then get out of here quick. Try explaining to a policeman that you’re part of the great war against demons—see where it gets you!”

Dervish examines the window with innocent curiosity. He pokes his fingers into the light, yelps when they disappear, clutches his hand back and wriggles his fingers, relieved to see them still in place.

Shark laughs. “I did that the first time too.”

“Have you ever stepped through?” Dervish asks.

“Once. Came back right away—didn’t want to get stuck over there.”

“What did you see?”

“A world like ours, only—”

“I have to go,” I cut in. They’d forgotten about me. Now they stare. “Beranabus. I’ve got to get back to him. Remember?”

“You want to step through the window?” Shark frowns.

“No. But I have to. I can find him when I’m in the demon universe.”

“What if the monster’s waiting for you on the other side?” Dervish says.

I shrug unhappily. “I don’t have a choice. I can’t find Beranabus here.”

“Won’t he come for you?” Shark asks.

“Maybe. But I’m not sure he can find me as easily as I can find him. I have to go,” I say, urgently this time, aware that the window might close while we’re arguing. “A demon stole my brother. I have to rescue him.”

I take a step towards the window. Shark puts out a large tattooed hand and stops me. “There’s no way I’m going to let a kid walk through that alone,” he growls. As my face crumples, he smiles. “So I’d better tag along, make sure you don’t come to any harm. Dervish?” He raises a questioning eyebrow.

Dervish studies the window again. Licks his lips nervously. Then nods quickly. “Yeah. What the hell. There’s never much to do here on a Saturday anyway.”

My eyes fill with happy tears. “Thank you,” I mumble.

“Never mind the thanks,” Shark sniffs. “Just be ready to fight.” And saying that, he grabs the collar of my T-shirt and hurls me through the violet window of light, back into the cauldron of the Demonata.

THE RELUCTANT DISCIPLE

I come out on top of a fluffy cloud. Through a break to my left I see land far below. My stomach drops as I picture myself falling through the mist, then the sky, hitting the ground hard and splattering. But the cloud holds, supporting me like the water in the first world I visited.

Shark steps through after me, Dervish just behind him. They yell with shock when they see what we’re standing on. Turn to dive back through the window. “It’s OK!” I shout. “We won’t fall.”

They pause, glance at me uncertainly, then realise I’m telling the truth—otherwise we’d have already dropped.

The now two-headed demon is on another bank of cloud ahead of us. When it spots us, it squeals with fear and bounds away. Shark starts after it, but Dervish calls him back. “We’re here to find Beranabus, not kill a stray demon.”

Shark pulls a face, loath to let the demon escape. Then he sighs. “OK, kid. Tell us how you plan to find him.”

“I’ll open a window,” I say, as the one we stepped through comes apart. “Just give me a few minutes to find the patches.”

“ ‘Patches’?” Dervish echoes, but I don’t answer. Looking around, I’m pleased to note that there are loads of patches of light in the air, despite the fact that we’re standing on top of a cloud. I start thinking about Beranabus, muttering his name softly, hoping he’s still alive and that I have the power to make the lights pulse.

For a few seconds—nothing. But before panic has a chance to set in, a pink square by my left foot blinks. Then a brown octagon. Soon, dozens of the patches are pulsing and I merrily set to work.

I’m aware of Dervish and Shark talking while I build the window. Dervish is complaining about the cold. His leather jacket is too small to button up properly—it’s for style, not warmth—and his bare chest is freezing in these icy heights.

“Use magic,” I tell him, recalling the way I instinctively repaired my broken arm. “You can warm up if you think yourself warm.”

Dervish is sceptical, but gives it a go, and moments later he’s beaming, even taking his jacket off and tying it around his waist.

“You must have been here a long time to know so much,” Shark says.

“Actually, I don’t think it’s been more than half a day,” I reply. “Though it feels longer. I’ll tell you about it later, if we have time.”

The window comes together smoothly under my guidance. I don’t hurry. Pleased to note I’m no longer hungry or tired. Marvelling at the way this universe works. I start wondering if we could float down to the ground from here, but then the assembled patches pulse as one and a brownish window opens. “Here we go,” I say smugly.

“I didn’t think windows could be opened that quickly or simply,” Shark says.

“It’s easy-peasy when you know how.”

Shark steps up beside me and looks back at Dervish. “Ready for the next leg of the tour?”

“Hurm,” Dervish says uncertainly. “Do you know where that leads?” he asks me.

“No. But Beranabus will be there.” I hesitate. “When I left him, he was in trouble, fighting a team of demons. We might have to help him. So be prepared, OK?”

“Yes, boss,” Shark laughs.

“Thanks for warning us,” Dervish says, then takes up a position to my left. Shark slides into place on my right. We step through the window.

It’s the same world where Nadia and I ran out on Beranabus. Night. Three moons shine, closer than the moon is to Earth in my universe. Too bright to see if there are any giant demons soaring overhead.

Corpses are scattered across the hard yellow ground. Demons in an advanced state of decomposition, most rotted to the bone. Either demons rot quickly here or this is one of those places where time runs faster than in the human universe.

I spy Beranabus working on a window. Sharmila is nearby, sitting next to a mound of freshly dug earth. I guess it’s Raz’s final resting place, that she and Beranabus—probably just her—dug a grave for the fallen Disciple.

I get a lump in my throat when I think about how Raz died, but there’s no time to cry. I didn’t believe I could be so matter of fact about the death of a friend, but I’m learning a lot here. One of the things is that in times of severe disorder, you can’t worry about the dead, only the living. I still think Art is alive. He’s the one I have to focus on. I can’t do any good for the dead Raz Warlo.

“Beranabus!” I call. “It’s me, Kernel. I’m back.”

The magician’s head whips round and Sharmila’s jerks up. They stare at me in disbelief, then at the two men with me. Then Beranabus cheers—the first time he’s acted like an ordinary human since I met him—and rushes across to pick me up and whirl me around.

“Kernel Fleck!” he booms. “You’re a wonder! I’ve been struggling to build a window to you for days. And here you pop up, cool as a breeze! You’re the most remarkable human I’ve met in centuries!”

He sets me down and I find myself grinning at him. I hadn’t liked the cranky magician before. But now I see he can be as emotional as any normal person. He simply hides his feelings better than most.

“Hello, Beranabus,” Shark says, stepping forward, hand outstretched.

Beranabus shakes the hand briefly, frowning. Then he points at Shark and says, “Octopus?”

“Shark,” Shark laughs.

“Ah. I knew it was something like that.” He looks at Dervish blankly.