Beranabus is waiting in a surprisingly scenic spot, lying on a pile of deep green grass next to a waterfall, beneath the shelter of a leafy tree. The only hint that this is another universe - blood, not water, flows from the waterfall.

"I thought you might come looking for me," he says, sounding more sad than smug. "I decided to rest here a while." He looks around. "I come here often. My mother liked this place. I feel close to her here."

"Was your mother a magician?" I ask.

"Not as such." He stares at the waterfall, stroking the petals of a fresh flower which he's pinned to his jacket. "She died not long after I was born. I used magic to find out about her later - that's how I learnt about this spot - but I never knew her when I was a child. As for my father..."

He snorts, then says with unusual softness, "I know what it's like to be lonely. To have no family. To feel out of place in the world. I hate myself for what I did to Nadia and for what I'm asking of you. I know how wretched her life was and what you're suffering now, because I've felt that way myself. I'd have spared you both if I could. But the universe demands sacrifice and pain of its champions. When there's no other way... when the fate of billions hangs in the balance... what choice do we have?"

I stare at the ancient magician, not sure how to answer. Before I can think of something to say, he barks a laugh, pushes himself to his feet and smiles, more like his old cynical self. "Come to be my assistant, have you? Couldn't fit in with the folks at home? Normal life not for you any more?

"You knew I'd return, didn't you?" I accuse him.

"I've lived and seen enough to know how difficult it is to settle for a small life when you're destined for greatness. The universe created you for a reason, Kernel Fleck, and it wasn't to waste your time in an ordinary job, among everyday people. Destiny is a determined opponent. Not many get the better of it."

"So what now?" I ask. "Do we go after Cadaver?"

"I don't think so." Beranabus frowns. "I'm angling more towards the idea of re-tracing the route he followed when he was on his way to Lord Loss'. Maybe we'll find something on one of the worlds he visited, or on a world we bypassed when you opened the window directly to him."

"Or maybe..." I stop, not wanting to say it. The window behind me has faded, but I could easily build another if I wanted. Find my parents. Try again. It's not too late to change my mind. But if I tell Beranabus of my suspicions, I can never return. I'll be his - the universe's - for life.

Beranabus studies me with one eyebrow raised, smiling as if nothing I say can take him by surprise, like he's waiting for me to make a suggestion so that he can say he's already thought of it.

I chew my lower lip, trying to make up my mind. I think about the photo again. Shiver then straighten up and put my theory to the test.

"I'm picturing Cadaver inside my head now," I tell Beranabus then look around. "Dozens of lights are flashing. I could open a window to him if I wanted."

I clear the demon from my thoughts and think about Beranabus. "Now I've got you in my head." My stomach sinks when I check the lights and my worst fears are realised. "Nothing's happening. No lights are pulsing."

"Of course not," he snorts. "I'm here with you. There's no need to open a window to find me."

"Right. Now I'll think about a waterfall on Earth - Niagara Falls." I concentrate. "Lots of pulsing lights again. But when I think about that waterfall of blood... nothing."

Beranabus is frowning. "What are you - "

"Picturing Sharmila," I interrupt. "Dervish. Shark. Lights pulse for all three of them." And for Nadia too, though I don't tell Beranabus that. "Now I'm thinking of myself - no flashing lights. And now... now I'm thinking about the Kah-Gash." I give it a full minute. Two. Five. Eyes shut, focusing hard, saying the word over and over. When I finally open my eyes, none of the lights are pulsing, and Beranabus is staring at me, trembling slightly.

"Nobody knows what the Kah-Gash was," the magician says softly, "or what sort of parts it was broken down into. I've always assumed the pieces would be power-charged stones or other objects of energy, but I guess they could be hidden in anything. Even in..."

"people." I finish, then take a deep breath. "The piece of the Kah-Gash... the weapon that can destroy universes... We've been close to it all along. Too close to recognise it. It's here now. It always has been."

Beranabus shudders, then steels himself. "Am I the one?"

"No," I say sadly. "I think it's me."