Out of the flat, down three flights of stairs, taking the steps two at a time, four on the last set. I slap the wall on my right as I fly past. Someone spray painted a giant arse on it months ago and I always slap it for good luck when I pass. Some of the neighbors have tried scrubbing it off but it's hanging in there, faded but defiant. I love graffiti. If I could paint, I'd be out covering the walls of London every night.

I land like a cat, cool in my new, totally black sneakers. There was a bit of red running through them when they first came out of their box, and the brand name shone brightly, but I carefully went over everything with a heavy-duty Sharpie. B Smith is nobody's advertising pawn!

It's not yet six, plenty of daylight left. I don't know what Mum was panicking about. Even if zombies were real, and even if they did attack here, they wouldn't show their faces for another hour, not if the news teams have got it right.

I check myself out in shop windows. Plain black T-shirt and jeans, no tags to show what make they are, threadbare in places, but worn in naturally by me, none of your bloody designer wear and tear.

I'm almost past Black Spot when I stop and backtrack. Vinyl's in there with his old man. Black Spot is a retro freak's paradise. They only stock vinyl records, along with clothes, toys, hats, and other bits and pieces from the dark ages. I even saw a video recorder in the window once.

Vinyl's dad loves all that twentieth-century crap. He won't let CDs or DVDs in his house, and as for downloads, forget it! They have a computer but all the music sites on it are blocked. He says the crackle of old records is what real music is all about, that digital tracks don't make the air throb.

I lean close to the window and tap on it softly. Vinyl looks up and scowls. He hates it when we spot him with his dad. Vinyl's old man is all right - he does his own thing and doesn't make a song and dance about it - but he's a weirdo. I think Vinyl secretly likes the records that his dad makes him listen to but he never admits that to us or defends his dad when we slag him off. As long as we don't take it too far. I started to make a joke once about his dad liking the small holes that you find in the middle of records. Vinyl very quietly told me to shut up. He didn't have to say any more. I'm not afraid of Vinyl but I know he'd wipe the floor with me if we fought. Why sign up for a beating if you don't have to?

I make a face and stick out my tongue. Vinyl gives me the finger, then says something to his dad. Old man Vinyl looks up, nods at me and smiles. I salute him, the same way I saluted Dad a while ago. Vinyl comes out, nudging the door open with his head.

"You're so cool," I gush, squeezing my hands together and making doe eyes at him.

"Get stuffed," Vinyl sneers.

We grin and knock knuckles.

"I like the hair," Vinyl says. "Number 3?"

"Sod that. Number 2."

"Hard-core."

Vinyl's got long, curly hair. He'd love to shave it but his mum would cry and he doesn't want to upset her. He's a soft git, Vinyl. But hard when he needs to be. There aren't many who get the better of him in a punch-up.

"How's the new school?" I ask.

Vinyl rolls his eyes. "I should have failed that bloody test."

"Bad?" I laugh.

"You wouldn't believe it."

Vinyl took a Mensa test in the summer. Turns out he's smarter than the rest of us put together. His mum went gaga - she thinks he's the new Einstein - and begged him to switch to a posh school. He hated bailing on us but she turned on the tears and he caved.

"What's it really like?" I ask as we stroll, punching each other's arm every now and then.

"All right," he shrugs. "I thought they'd be full of themselves but most aren't much different from us. I'm doing okay, not the best, not the worst."

"What about the teachers?"

He shrugs again. "They wouldn't last long in our place. I'd give them a week - they'd be head cases after that."

Vinyl still thinks he's one of us. And at the moment he is. But that will change. You can't switch schools and carry on as if nothing's happened. He'll make new friends soon and start hanging out with them. Another few weeks and we won't see a lick of him. Way of the world.

"You must be crapping yourself," I tell him.

"What are you talking about?" he frowns.

"The zombies."

"What about them?"

"They go for freaks with big brains."

He laughs sarcastically. "Know what I like about you, B?"

"What?"

"You'll be dead one day."

We snicker, knock knuckles and head for the park.