"No," Mark wheezes. "This can't be right. I'm a zom head. I was attacked. I was killed. There's been a mistake."

The zombies - and that's what they are now, all human semblance discarded - don't reply. They're shuffling closer, eyes steady, ready to feed.

"Get back," I snarl, leaping to my feet and pushing Cathy away. I step between Mark and the others. "You're not going to do this. I'm hungry too. I can smell him just like you can, and it's driving me wild. But I won't harm him and I won't let you lot either. You have to control yourselves. This is Mark."

"Worm," Cathy gurgles, grinning crookedly. "Wriggle, little worm."

"No!" I roar, slamming my hands together, trying to startle them back to their senses. "Stop. Think. Don't give in to the hunger. Peder. Gokhan. Tiberius." I turn pleadingly to the ginger-haired teenager. "You stood by my side. You fought for my life. Do the same for Mark. You have to. He's one of us." A memory clicks in. "We accept him! Gooble gobble!"

Tiberius pauses and his eyes clear slightly.

"It must have been an experiment," I babble. "They wanted to see if they could hide a human among us. They told him he was a zombie. They covered him up so that we couldn't smell him, hear his heartbeat or see him breathing. They must have given him drugs to keep his eyes open, dry out his mouth, stop him from sweating, make him look like he was a revitalized."

"But he's not," Peder growls. "He's human."

"I didn't know," Mark wails. "I thought... they told me... I never even guessed! B, you've got to stop them. Don't let them eat me. Please, B, I want to live, I don't want to - "

"Shh. I'm trying." I concentrate on Tiberius, hoping that if I can reach him, he can help me get through to the rest of them. "All right, he's not a proper zom head, but he's still one of us. He's been living alongside you guys for months. You can't turn on him as if he doesn't mean anything to you."

"Worm," Cathy leers again, reaching out for the trembling boy.

I slap her hands away. "I know you don't respect him, you bully him, you treat him like a worm. But he's still part of the gang. You won't attack one of your own. You're not monsters. It's the hunger. You have to fight it. You - "

Gokhan smashes a fist into my jaw and I stagger sideways. Mark shrieks and the sound excites them. They press forward. Before they can target him, I'm back between them, punching and kicking, screaming abusively. I'm not going to accept this. I let Tyler Bayor die. I won't let it happen to Mark too.

"Stop!" I yell. "You don't know what you're doing!"

Peder grabs the neck of my T-shirt and pulls me in close. His eyes flash as he grins at me. "Yes we do," he hisses.

"Tiberius!" I bellow. "Help me! We have to fight together! You have to - "

Tiberius puts a finger to my lips and says, "Hush now." Then he grabs me from Peder and throws me aside.

Mark screams. "No! God! Help!"

But not even God can help him now.

The zombies fall on the boy. They dig their fingers into his skull and tear it open. Ram claws into his brain and scoop it out. They ignore his screams, his whimpers, his pleas, the feeble thrashing of his arms and legs.

And all I can do as the beasts feast and Mark dies wretchedly before my eyes, calling my name, begging for mercy, is beat the floor uselessly with my fists and howl insanely at the cruel injustices of this monstrous, twisted world.