Nadia falls silent. She squats with her face averted. Raz and Sharmila look anxious and move away to discuss the revelation in whispers. I stay where I am, watching Beranabus work. I'm not that disturbed by Nadia's prediction. This is all crazy anyway. Death's only to be expected in a place like this.

Beranabus is having difficulties with the window. The patches of light are slotting into place, but slowly. And while most of the patches he's joined together are pulsing at the same rate, some aren't. If he could see the lights, it would be simple, but he can't. He has to create the window using complicated, time-consuming spells.

I can't understand why the magician and the others can't see the lights. They're more powerful and experienced than me. So why am I the only one who can view the assembly of the window?

While I'm pondering that, a few more patches of light slot into place. A shimmer runs through the panel. The various colours vibrate a few times in unison. Then they all turn yellow and stop pulsing.

"Ah!" Beranabus grunts. He turns, claps his hands to get everyone's attention, then waves at the window of yellow light, now visible for all to see. Raz and Sharmila approach with suspicion. Nadia hangs back.

"Do you know what is through there?" Sharmila asks.

"Another world," Beranabus says.

"Can you be more specific?"

He shrugs. "I was searching for Cadaver, not a specific world. Until we pass through the window, I've no way of telling where we'll emerge." He raises a bushy eyebrow. "Nervous, Miss Mukherji?"

"Nadia told us about her vision," Raz mutters, gaze lowered. "About the Kah-Gash and your quest. She said there would be fighting and death."

Beranabus snorts. "That girl should learn to keep her mouth shut." He glares at Nadia, then shrugs. "You chance death every time you face a demon. That's nothing new."

"But we have been told that on this occasion it definitely lies in wait," Sharmila says. "That is different."

"Not really," Beranabus says. "Nadia has no idea who will die. It could be anyone - you, her, me, the boy. Maybe it will be all of us." Beranabus looks at the window and scowls. "You can quit if you wish. I've no time for cowards. But consider this - the Kah-Gash can destroy a universe. If you withdraw and the piece of the weapon we're chasing falls into the hands of the Demonata..."

"You really believe the Kah-Gash exists?" Sharmila asks.

"Aye."

Sharmila and Raz share an uneasy glance then Raz nods, followed - after a pause of several seconds - by Sharmila.

"How about you, Fleck?" Beranabus turns his small dark eyes on me. This is the first really close look I've had of him. His skin is pale, but covered in dirt and grime. Lots of wrinkles, and a few old scars and blemishes. Untidy black hair, clumps of grey and white, his beard trimmed unevenly. His hands are clean, in contrast with the rest of him, but the tight flesh round his knuckles is covered by lots of blotches and faded scars. Dusty, dirty clothes. He wears a small flower in a buttonhole on his jacket, which looks pathetically out of place. Several of his teeth are missing, and the rest are crooked and rotten. He smells bad, like something that has half decomposed. I don't like him and I don't trust him. But he's the only hope I have of finding Art.

"I'm coming," I say, trying to sound more positive than I feel.

"Then it's decided," Beranabus says and steps through the yellow window. Sharmila follows, then Nadia - reluctantly, chin low.

Raz claps me on the back. "After you."

I face the window of yellow light. Think about the demons that might be waiting on the other side. Take a breath. Hold it. Step through.

A desert world. It's night, but lots of stars are glittering, so I can see clearly in all directions. Beranabus is magically searching for Cadaver, standing very still, eyes closed. After a few minutes he shakes his head. "He's been through here but didn't stop." Rolling his shoulders, he spits on his hands, scuffs the sand with his feet, then starts on another spell, to open a new window and follow the demon to whatever world it fled to next.

The patches of light round us are glowing steadily when Beranabus begins. Soon after he starts searching for Cadaver, several pulse and move towards a spot in front of him. As he chants, more pulse and others drift in from afar to be added to the patchwork panel. Beranabus is piecing them together with spells. But if he could see them like I could, and move them directly by hand...

I think about offering my help, but I'm afraid he'll laugh at me, so I keep my idea to myself. After a while I realise it's been ages since I ate or drank, yet I don't feel hungry or thirsty. I mention this to Raz, who's lying on the sand close by, idly gouging out shapes with a finger.

"I noticed that too," he says. "And although I have been here a day or two, I don't feel sleepy. Our bodies must work differently in this universe. It is a place of magic and you can do many incredible things with magic." He waves a hand over the sand and a sandcastle slowly thrusts upwards, turrets, a moat, tiny sandy guards on the ramparts.

"Cool!" I gasp. "Do you think I could...?"

"Try," he says. "I didn't know I could do that until just now."

Excited, I sit and think about a castle even bigger and grander than Raz's. I wave a hand over the sand, summoning my masterpiece.

Nothing happens.

Disappointed, I decide I'm being too ambitious, so I picture a smaller castle, with fewer turrets and troops. Again, nothing happens. I keep lowering my expectations, demanding less and less, until finally I ask for the simplest sandcastle possible. The sand ripples, then spits up a meagre glob.

Raz laughs. "Don't worry. Gifts vary. Magic shows itself uniquely in each person. I can create sandcastles. Perhaps you can change shape or make rain."

"Really?"

"It's possible."

I close my eyes and think about what sort of an animal I'd like to turn into.

Later. No luck with the shape-changing or making rain. If I have a magical gift, it must be very unique!

Beranabus is hard at work on the window, which seems to be nearing completion. I'm lying next to Nadia, Sharmila and Raz close by. Nadia's been telling us about her life with Beranabus, the ways of demons, how to fight them.

"Where are they all?" I ask during a lull. "This is the second world I've been to, and apart from the trees, I haven't seen any demons."

"In a hurry to spot some?" Sharmila chuckles.

"No. I was just wondering. Where do they live?"

"They could be anywhere," Nadia says. "Beneath the sand. All around us and invisible. On the other side of the world. There might be thousands here or only one. It varies. Some demons create a world just for themselves. Others - "

"Demons can create worlds?" Raz interrupts.

"The stronger ones can. Most just rampage through existing realms, but demon masters have the power to make new worlds and even self-contained universes."

"Do they make the stars as well?" I ask.

Nadia smiles grimly. "Those aren't stars."

We stare at her then up at the sky. It's peppered with glowing dots. They're not like the stars in our universe - they're bigger, brighter, closer, and many move across the heavens like meteors. But they can't be anything other than...

"They're demons," Nadia says.

"They can't be!" Sharmila protests.

"Nevertheless, they are."

"But..." Sharmila gazes up at the sky, horrified. "To be able to see them from here... they must be enormous!"

"Yes."

"Are they demon masters?" Raz asks.

"A few, perhaps, but most are just incredibly large demons who sail the skies, looking for others to torture and destroy. They don't usually bother with the likes of us - we're too tiny - but occasionally one might decide to squash us like ants." She chuckles humourlessly. "When that happens, you get out as quick as you can. There's nothing else you can do against a star-sized demon."

I gawp at Nadia, then at the sky, filled with monstrous shapes. Suddenly, this place feels a lot more dangerous than it did a few minutes ago.

The next world is a giant, needle-shaped chunk of rock. The top is flat and lumpy, sixty or seventy feet in diameter. A hot wind howls round it, biting at us, threatening to rip us loose and cast us over the edge.

Beranabus curses and crouches. We copy him. "I've been here before," he says, speaking as quietly as he can, yet loud enough to be heard over the howling wind. "It wasn't somewhere I ever wanted to return to."

The anxiety in his tone affects us all, even Nadia, who starts murmuring the words of a spell - I think it's meant to protect us, or at least her.

"I'll keep the window to the other world open as long as possible," Beranabus says. "That way, if we come under attack, we can..." He stops. The yellow window of light has blinked out of existence. Beranabus growls and a look of disgust crosses his face.

"What's happening, master?" Raz asks nervously.

"We've been ensnared," Beranabus says, rolling up the sleeves of his jacket and shirt. "Cadaver's led us into a trap."

"Is he here?" Sharmila asks, looking round uneasily.

"No. He's not welcome in this place. But he must have tipped off the Kallin. They were waiting for us. They destroyed the window."

"Who are the Kallin?" Raz yells.

"Crawl to the edge," Beranabus says, turning away from us and sitting cross-legged. "Have a look. Nadia," he adds, "marshal them. Help them fight. Buy me time. I don't think I'll be able to open a new window fast enough, but let's not die cheaply."

He starts muttering spells, lips moving at a tremendous speed. Around him, patches of light pulse and blink, then move together, a bit faster than before, but not greatly so.

We look at each other then crawl towards the edge of the needle. The wind increases as we get closer. We lie flat on our stomachs, inching forward. I feel sick. I don't want to look over the edge. But I must.

I don't suffer from vertigo, which is good because it's a long drop. And I mean L-O-N-G! I can't see the base of the needle. It seems to be suspended in mid-air, and for all I know, it is. We're in a universe of demonic magic. Who says giant needles of rock need to be rooted to the ground?

But the stomach-churning drop isn't the worst thing. Slithering up the face of the rock are... things. Hundreds and thousands of small, long, black, hairy, spider-like creatures. Except they can't be spiders because they have no legs. They move more like worms. Slithering towards us, an army of them. The Kallin.

One of the monsters leans back and raises its face to us. I see dozens of tiny eyes and a wide mouth. As I watch, the mouth stretches like a snake's, the thing opening its jaws far wider than its body. There are fangs inside the mouth. More than I can count.

Something taps my shoulder. I scream, whipping round. But it's only Nadia. She grabs me before I roll off the top of the needle, drags me away from the edge to where Sharmila and Raz are waiting.

"We're in trouble," she says simply. "There are thousands, so we can't fight them. Our best hope is to block them. That means a barrier of energy, to keep them back."

"Will that work?" Raz asks.

"We'll soon find out. Now, we have a few minutes, so let's see what we have to work with. I want each of you to create a personal barrier. Imagine yourself at the centre of a bubble of energy. Let your magic flow into it. Once I have an idea of your power, I can coordinate a spell and unite our magic forces."

Sharmila and Raz close their eyes and focus. I don't have a clue what I'm doing, but I follow their lead. I concentrate, trying not to think about the Kallin, willing a barrier into place, praying I have more success than with the sandcastle.

A few seconds later Nadia says, "Let's see what we have."

I open my eyes and spot her throwing a punch at Raz. Her fist stops several inches short of his face. She tries again - same result. She grunts with satisfaction. Jabs at Sharmila. Her fist slows but doesn't stop. Lightly smacks into Sharmila's chin, not harming her but getting through the barrier. "Try to strengthen it," Nadia says. Jabs a second time. Again, she penetrates Sharmila's barrier, but with more difficulty. Pulls a so-so face.

"Now you," she says to me. Makes a fist, starts to throw a punch... then stops. Sticks out her right index finger. Pokes at me softly. Prods my nose. Smiles. "Guess you're out of this one.

"It's not my fault," I grumble. "I'm not used to magic. I don't know how to make it work."

"It's OK." She tweaks my nose. "You can be our second line of defence. Watch for any demons getting through. If one penetrates the barrier, do your best to kill it while we plug up the hole it creates."

"How do I kill them?" I ask.

"With magic. You can stamp on them, choke them, firebolts of energy - whatever comes most naturally to you. But there has to be magic as well. You can't kill a demon by physical force alone."

"What if I can't make it work? What if - "

"Kernel!" she snaps. "We don't have time for hysterics. Just do your best, like when you escaped from the demon tree."

She draws Sharmila and Raz aside to prepare them. While they're discussing magical barriers, I creep to the edge of the needle to monitor the advance of the Kallin. They're a lot closer than a couple of minutes ago. Not so small now that I have a better view of them. Two or three feet long. Making soft squeaking noises, barely audible over the roar of the wind.

I think about throwing myself off, taking the easy way out, not waiting for them to clamber over me and rip at me with their fangs. One short step or leap... a few seconds or minutes of freefall... then no more worries. Unless there's nothing to freefall to. Maybe there's no ground in this part of the Demonata's universe. I might bob back up or fall forever, a lifetime of falling... screaming... thrashing.

"They're almost to the top!" I shout, putting the dark thoughts behind me. "Half a minute and they'll be all over us!"

"Get back here," Sharmila calls. They've gathered close to Beranabus, who's concentrating on the slowly forming window. I crouch next to Raz, feeling safer beside him than Sharmila, since he was able to construct a stronger barrier.

"Here we go," Nadia says shakily. She half closes her eyes. So do Sharmila and Raz. There's a shimmer in the air a couple of feet in front of us. Then nothing. I wonder if the spell has worked, if we're protected or not. Then the first of the Kallin wriggles over the edge of the needle and launches itself at us, mouth wide, fangs bared, screeching with hunger and hate.