Artery and Lord Loss hurl themselves at Beranabus. The scorpion-shaped Spine targets Kernel, eager to finish the job which it doesn't remember starting. Femur sets its sights on me.

It's almost comical watching the rabbit bound towards me. It's like a sick cartoon, Bugs Bunny gone batty, leaping on people to plant a great smacker of a kiss on them. Except this creature's acidic smooch will melt a person's face and leave them a smouldering, sizzling mess-not the sort of fare you'd usually find in a Looney Tunes flick.

Femur spits acid in mid-air. It spurts towards me, a sheet of liquid death. Directed by the magic inside me, I wave my left hand at the deadly juice. It divides and hisses past my head, hitting a couple of stalagmites behind me, quickly eating into them and eroding the work of thousands of years.

The rabbit's leap brings it within reach. I grab its neck and twist sharply. The neck breaks and I toss the creature away. It gurgles, then heals itself and gets up. I smile, grown bold by the combination of magic and ease with which I shrugged off the demon's attack. I beckon to it. "Try again, lettuce-muncher!"

As Femur tenses its rear legs and works its lips over its gums, Kernel stumbles past me. Spine is on his head, jabbing its stinger at his eye sockets. He's batting it away. "Let me know if you need help!" I shout. Then Femur leaps and spits acid again, and I have to focus on that.

As I fend off the rabbit I spot Beranabus. Lord Loss has the magician within his grasp, all eight arms wrapped around him, a spider devouring a fly. Artery is on Beranabus's back, chewing at his shoulders. One of his hands is under the magician's skin. I see knuckles moving within the flesh.

Maybe it's a trick of the light, but Beranabus's skin appears to be a different colour. There's a purple tinge to it and his eyes seem to have grown and turned a dark grey shade. And the blood streaming from the hole in his shoulder that Artery's chewing at... is it yellow?

As I'm studying Beranabus uncertainly, Femur bounces up once more, spraying its corrosive poison. Snapping back to attention, I freeze the acid, then punch through the solid panel of ice and grab the rabbit's ears. "Enough of this crap," I grunt and drive my left fist down the demon's throat.

Femur's eyes bulge alarmingly. It chokes and tries to gnaw through my arm. Cuts the flesh up pretty bad. Pain flares, but I numb myself to it and focus on my hand deep in the rabbit's guts. I fill the fist with magic, then let it explode, incinerating the demon from the inside out. Femur gasps, mouth slackening, blinking furiously. Its legs shake. Acid dribbles over my forearm, but I turn it to mist before it harms me.

The rabbit's ears rip loose and I throw them away. They flop around on the floor of the cave for a few seconds, then fall still as life leaves Femur's body. Its flesh turns a dark red colour, then crumbles away like ash. I pull my arm free and study the mess, lips curled with disgust. I start towards the waterfall to wash clean and sluice out my wounds. Then I have a better idea and direct magic at my arm. Seconds later-spotless, unmarked flesh. Coolio!

My first thought is to go to Beranabus's aid or help Kernel with Spine. But then the magician's warning kicks in. Juni Swan is public enemy number one. She has to be stopped. I'm not sure I can do it-the doubts swim back inside my head-but I have to try.

Skirting Beranabus and Lord Loss, I hurry to where the transformed Juni is chanting into the crack, arms spread wide, words coming fast and furious. For a second I think I glimpse a face in the rock, just within the opening of the crack. But then it's gone and I'm not sure whether it was Bec, the first of the demon hordes or a trick of the light.

I don't want to touch Juni-the thought of physical contact with her repulses me. So I bring my hands together and summon a bolt of magic to fire instead. Nothing happens. I can feel the magic, but it's like there's a barrier between us, blocking the lines of communication. Then I realise what the problem is-the werewolf. There's a full moon. Beranabus told me I'd have no trouble suppressing the wolf now, but it would always be there, scratching away beneath the surface, whining, trying to break free.

"No time for games, wolfie," I mutter, and mentally drive the beast deep down within me, to howl in silent, imprisoned protest for at least another month. The magic burns brightly inside me as soon as the way's been cleared. Once again I tell it what I want and this time I feel energy gather in my hands. Pointing them at Juni, I unleash the power. A huge ball of magic shoots straight at her- then hits an invisible barrier and crackles away into nothing.

Juni glances around, sneers at me, carries on chanting.

"'Ubbs!" Dervish grunts as I prepare a second blast. He's straining to get to his feet. Beside him, Bill-E's staring at me as if he doesn't know who I am. "'Ubbs!" Dervish shouts again, mouth constricted by his gag.

I wave a hand at my uncle and brother. Their gags and the ropes binding them burn away. As soon as he's free, Dervish thrusts himself up and throws his arms around me. "I thought you were dead!" he cries, burying his head in my chest.

"Not me," I grin, hugging back hard, momentarily forgetting the fight and all that's at stake. It's so great to see him again, to have him hold me, to be home and with the closest thing to a father I have left. If the world ended here and now, for me it would be a good end.

"Grubbs?" Bill-E says hesitantly, studying me warily. "Is it really you?"

"Sure is... little brother." I smile at him awkwardly.

"You should have told me," he growls, pointing a finger. "All this time... if I'd known... all my life I thought I was alone. You should have told me!"

"I know," I sigh. "I was a fool. Forgive me?"

"No way, baldy," he smirks. The smile quickly fades when he spots the woman next to the crack. "Her!" he growls, finger swivelling. "Is that Juni?"

"Yes," Dervish snarls. "The face might be different, but the evil stench is the same. She told us you attacked her, Grubbs. That after killing Ma and Pa Spleen, you..." He pauses. "You didn't kill them, did you?"

"Of course not," I huff indignantly, not admitting that I'd thought the same thing myself.

"I told you," Bill-E says proudly. "I knew Grubbs wasn't a murderer."

"I didn't think so either," Dervish mutters. "But she was so convincing. Sobbed hard when she came back. Said she saw you murder them, that you tried to kill Billy, but she lured you away. She was a pillar of strength. Guided us through the burials. Comforted Billy. Helped deal with the police enquiries. I loved her more than ever.

"Then she said we could find you, that she could use the magic of this cave to locate you. Fool that I was, I believed her. Billy had moved in with us. Juni said we should bring him along, that it might help with the spell. I didn't see how, but she was stronger than me. She knew more about magic. I trusted her.

"When we got here, the demons jumped us. Juni clubbed me over the back of my head and they trussed us up. Lord Loss told us he was going to open the tunnel. A sacrifice had been made and the killer would join with the rock and keep the tunnel open. He said he'd let the Demonata cross, then murder me slowly. Said he had something extra special in mind for Billy. He-"

"Dervish," I interrupt softly. "If she finishes that spell, we're in for seventy-seven different types of hell. We need to kill her. Now."

Dervish nods grimly. "OK. You work on bringing down the barrier. I'll handle the rest."

"You're sure?" I ask, grateful that he's offering to take the horrible task out of my hands, but wanting to provide him with an alternative if he feels he can't slaughter the woman he once loved.

"I'd fight anybody who tried to kill her before I had a shot," Dervish says, and the burning hatred in his expression scares me.

One quick glance behind. Kernel's pinned Spine to a stalagmite and wrapped the demon's stinger around the needle of calcium. He's pummelling its face with his right fist, holding the tip of the stinger in place with his left hand.

Beranabus-his flesh an even darker shade of purple than before-is locked in combat with Lord Loss, the demon master howling like a dog, the snakes in his chest cavity lashing the magician with their forked tongues. Artery has worked both hands under Beranabus's skin and is trying to get his head in too, to chew his way through the bones and into the meaty innards. It's not looking good for the old magician, but I know he'd rather we killed Juni and let him perish than go to his rescue and leave her free to open the tunnel.

I let magical energy charge within my fists again-charge blast! Charge-blast! Charge-blast! Dervish is standing a metre or so ahead of me, out of the way of the explosions, fingers twitching, eyes locked on Juni, eager to squeeze his hands around her throat. Bill-E is watching my back, keeping track of the demons, making sure none springs on me unawares.

The barrier starts to give. Each ball of magic crackles louder and lasts longer when it smacks against the energy field. A few more and she'll be at our mercy.

"Master!" Juni screams. "Help me! I need more time!"

"Spine!" Lord Loss roars. "Femur!" I sense him looking for his familiars. Then he curses. "Attack them, Artery. Leave Beranabus to me."

Ripping sounds. Bill-E yells a warning. "Grubbs! Look out! He's-"

Artery lands on my back and I stagger. Before I can turn to deal with the hell-child, Dervish grabs his legs, swings him round and batters his head off a low-hanging stalactite. The skull splits down the middle and brains ooze out. Lice fall from the fiendish baby's crown and scuttle around on the ground. Dervish twirls the demon overhead a couple of times, then throws him far across the cave, where he smashes hard into a wall and collapses. Artery will recover, but it'll take him a minute or two. That should be more than enough time.

"Master!" Juni screams again, spitting the cry out between the words of the spell that she's chanting. Her real face looks far less commanding than the one she wore when she was pretending to be our friend. It carries the scars of fear and low character. "One more minute. That's all I need."

Lord Loss howls louder than any wolf, then reluctantly releases Beranabus and whacks him aside. I hear a whoosh as he propels himself towards me. "Grubbs!" Dervish yells.

"Just a second," I mumble, taking aim, letting off one last blast of energy. It sounds like a gunshot when it hits the barrier-then crashes through and connects with Juni, knocking her to the floor.

I open my mouth to cheer, but Lord Loss is on me before I can, cursing foully, eight arms around my mouth and throat, squeezing, tearing, intent on pulling me to pieces and choking me all at once.

Gasping for air, I grab two of his arms, focus my magic and tug with all my strength. The arms rip free of their sockets. Lord Loss wails and tries to reattach them, but I send fire shooting up the limbs and they burn away to nothing before he can restore them.

Dervish steps in to help. "No!" I yell, feet dangling a few centimetres above the ground as a furious Lord Loss clutches me to his chest, where the snakes fight with each other to bite out my eyes. "Kill Juni! I can deal with-"

The demon master gets a few mangled, lumpy, bloody fingers into my mouth. They lengthen and extend back into my throat. Out of the corner of my eye, I see Dervish wavering. His natural instinct is to help me. But then he sees Juni back on her feet, muttering the spell again. With a wild curse he goes after her.

I bite off the fingers and spit them out. Lord Loss screams obligingly. One of the snakes digs its fangs into my bald skull and rips out a chunk of flesh. I snatch the snake from its heartless home and chew its head off. I'm starting to enjoy this biting business.

Lord Loss's six remaining arms tighten around my body. I feel the bones of my ribcage creak and groan. I know that if the demon maintains this pressure, the bones will snap and pierce my lungs and heart, and that will be the end of me. But it doesn't matter. I'm buying time for Dervish. Stopping Juni is my only reason for being here, for living. If I have to die to thwart her evil plans, that's just bad luck. I'll give my life gladly.

But before I can die nobly, Beranabus stumbles back into action. Picking up a stone, he invests it with magic and hurls it at Lord Loss's head. The stone pierces the demon master's flesh and bone, and ends up sticking half in and half out of the monster's skull, just above his left ear.

Lord Loss shrieks with pain and rage, then twirls and throws me at Beranabus. I collide with the magician and we sprawl across the ground. Lord Loss starts after us, then remembers Juni. Hesitating, he looks over his shoulder. Juni's wrestling with Dervish, shouting the spell even as they battle. Dervish is striking her hard, weeping, hands clenched together to form one mighty club. Juni's pockmarked, pasty face has been smashed to a pulp. Her hair and skin are flecked with blood, and her eyes are almost invisible behind her mashed flesh.

As Lord Loss turns to help, she stops chanting and smiles at Dervish. Her flesh ripples, changes colour, and she looks like the old Juni Swan again, only battered and bleeding. "Dervish, my love," she wheezes. "Please stop. You're hurting poor Juni."

"You betrayed us!" Dervish roars, tears coming harder than ever.

"I made a mistake," Juni murmurs. "I love you, Dervish. Please don't hurt me. I can make this right if you give me the chance."

Dervish stares at her, hands dropping, fury leaving his body, shoulders sagging. He takes a step forward. I think he means to hug her. That scares me, but not as much as what I suddenly spot happening overhead-the rock around the crack has started to pulse! Light is shining from deep within. And it's beginning to split wider apart.

"Dervish!" I yell. "She finished the spell. The demons are coming. You have to kill her!"

Dervish stops moving, but doesn't bring his hands together. Beranabus throws himself forward desperately. Lord Loss grabs him and laughs.

Skittering footsteps behind me. I half turn and spot Artery leaping, three sets of sharp teeth gnashing savagely. I raise my arms-too late. The demon strikes me in the chest with his tiny feet. I fly across the cave and smash into the rock at the back of the waterfall. Come up spluttering and cold, my leaf-suit soaked through and disintegrating, the water cutting out the sounds and sights of the cave.

I drag myself clear of the waterfall as Artery bounds towards me. He leaps to kick me again, but this time I grab him by his childish torso and hold him at arm's length, trying to find the strength to kill him, but too exhausted and dispirited. I glance around wearily, looking for help or inspiration.

Kernel is still out of the main action, unable to kill Spine, struggling to keep the demon pinned to the stalagmite. Lord Loss is bearing down mercilessly on Beranabus, squeezing tightly, snakes more active than ever. The demon master's laughing triumphantly, confident of victory. The opening in the rock is pulsing faster and faster, the colours and shades of light changing with every pulse, the mouth of the crack stretching, widening, extending. A magic-laced wind whistles up out of nowhere. I feel it blowing past me, towards the hole. Soft at first, but growing steadily, sucking up dust and bits of grit, sending them shooting down the crack. Bill-E's scrabbling away from the hole, moaning, sensing disaster.

And just beneath the crack-what will soon be the entry point for hundreds of demons-Juni Swan is kissing Dervish, her luminous white hair billowing out in a fan shape, gusting away from her skull in the ever-increasing breeze.

"My love," Juni gurgles, pulling back from him slightly, pink eyes twinkling maliciously. She strokes his cheeks, smiles seductively, kisses him again. Dervish is motionless, mesmerised, under her spell. Moving her head to his shoulder, she murmurs into his throat, "You could never harm your Juni. You love me, as I love you. What savagery, hitting me like that. But I forgive you. I love you too much to bear a grudge."

Her fake flesh has already healed and is as smooth and white as ever, though a few streaks of blood remain. She looks beautiful. It's strange, but unconcealed evil suits her. She's more stunning now than she ever was when she was pretending to be good.

I try shouting a warning, but I don't have the strength. Holding Artery at bay is all I can manage.

"I'll take you to the universe of the Demonata when this is over," Juni promises Dervish. "You'll have to be killed eventually, but there's no rush. I'll show you such wonders and treat you so sweetly, you won't care about dying. In fact you'll die gladly, to please me. Won't you, my love?"

Dervish stares at her blankly. Then Bill-E screams. "Dervish! I'm afraid!"

Juni laughs. "Don't worry, silly Billy, I haven't forgotten about you. How could I? You're the most important-"

Dervish grabs Juni by the waist and picks her up as if she's weightless. "No!" she screams, lashing out at him but unable to connect because of the angle he's holding her at. Dervish lunges away from the pulsing rock, struggling against the wind. Juni's hands stretch upwards, searching for magic. Her lips start on a new spell. Lord Loss shouts with alarm and springs away from Beranabus.

But Dervish is too quick for both of them. He looks around. Takes a couple of steps to his right, holding Juni high above his head. Then slams her down with all his strength on top of a small stalagmite.

The tip pierces Juni's flesh and slices in through the skin of her back-then bursts through her chest a moment later. Dervish cries out and falls away, staring with wonder and disbelief at Juni as blood spurts and her legs and arms thrash, as if he doesn't know how she got there.

"My swan!" Lord Loss howls, flying to her side.

"Master..." Juni groans, her mouth full of blood. "Help... me."

Lord Loss reaches out to her, then stops and studies the wound. He shakes his head softly, sorrowfully. "I cannot," he says.

Juni stares at him incredulously. Then her expression clears. "I understand. Thank you, master. For... everything you showed me... all that you did for me... I offer my everlasting gratitude... and love."

Lord Loss stretches out a single arm and touches Juni's cheek with his clammy fingers. He's smiling sadly, but it's not his usual mocking smile-this one is almost human. "I will miss you," he mutters.

"And I..." Juni shudders and her eyes go wide. "Death!" she wheezes. "It's here. I sense it. I... no! Don't let it take me, master! I want to be free. Don't..."

She stops. Her mouth and eyes freeze. Lord Loss bends, kisses her forehead, then floats back a few paces. "Goodbye, sweet swan," he murmurs, and that's when I know for sure she's dead, though it's not until I hear Beranabus chuckling softly that I realise what that means.

The key has been eliminated... The tunnel can't be opened... We've won!