Although, he had to admit, it was dreams during the day, too. Dreams so real that they filled his eyes and ears.

The planes ...

The bombs ...

And the fossil fly. Why that? There'd be these nightmares, and in the middle of it, there'd be the fly. It was a tiny one, in a piece of amber. He'd saved up for it and done a science project on it. But it wasn't even scary-looking. It was just a fly from millions of years ago. Why was that in a nightmare?

Huh. School teachers? Why couldn't they be like they were supposed to be and just chuck things at you if you weren't paying attention? Instead they all seemed to have been worrying about him and sending notes home and getting him to see a specialist, although the specialist wasn't too bad and at least it got him out of Maths.

One of the notes had said he was "disturbed". Well, who wasn't disturbed? He hadn't shown it to his mum. Things were bad enough as it was.

"You getting on all right at your grandad's?" said Yoless.

"It's not too bad. Grandad does the housework most of the time anyway. He's good at fried bread. And Surprise. Surprise."

"What's that?"

"You know that stall on the market that sells tins that've got the labels off?"

"Yes?"

"Well, he buys loads of those. And you've got to eat them once they're opened."

"Yuk."

"Oh, pineapple and meatballs isn't too bad."

They walked on through the evening street.

The thing about all of us, Johnny thought, the sad thing is that we're not very good. Actually that's not the worst part. The worst part is we're not even much good at being not much good.

Take Yoless. When you looked at Yoless you might think he had possibilities. He was black. Technically. But he never said "Yo", and only said "check it out" in the supermarket, and the only person he ever called a mother was his mother. Yoless said it was racial stereotyping to say all black kids acted like that but, however you looked at it, Yoless had been born with a defective cool. Trainspotters were cooler than Yoless. If you gave Yoless a baseball cap he'd put it on the right way round. That's how, well, Yoless was. Sometimes he actually wore a tie.

Now, Bigmac ... Bigmac was good. He was good at Maths. Sort of. It made the teachers wild. You could show Bigmac some sort of horrible equation and he'd say "x=2.75" and he'd be right. But he never knew why. "It's just what it is," he'd say. And that was no good. Knowing the answers wasn't what Maths was about. Maths was about showing how you worked them out, even if you got them wrong. Bigmac was also a skinhead. Bigmac and Bazza and Skazz were the last three skinheads in Blackbury. At least, the last three who weren't someone's dad. And he had LOVE and HAT on his knuckles, but only in Biro because when he'd gone to get tattooed he fainted. And he bred tropical fish.

As for Wobbler ... Wobbler wasn't even a nerd. He wanted to be a nerd but they wouldn't let him join. He had a Nerd Pride badge and he messed around with computers. What Wobbler wanted was to be a kid in milk-bottle-bottom glasses and a deformed anorak, who could write amazing software and be a millionaire by the time he was twenty, but he'd probably settle for just being someone whose computer didn't keep smelling of burning plastic every time he touched it.

And as for Johnny ...

... if you go mad, do you know you've gone mad? If you don't, how do you know you're not mad?

"It wasn't a bad film," Wobbler was saying. They'd been to Screen W at the Blackbury Odeon. They generally went to see any film that promised to have laser beams in it somewhere.

"But you can't travel in time without messing things up," said Yoless.

"That's the whole point," said Bigmac. "That's what you want to do. I wouldn't mind joining the police if they were time police. You'd go back and say, "Hey, are you Adolf Hitler?" and when he said, "Achtung, that's me, ja" ... Kablooeee! With the pump-action shotgun. End of problem."

"Yes, but supposing you accidentally shot your own grandfather," said Yoless patiently.

"I wouldn't. He doesn't look a bit like Adolf Hitler."

"Anyway, you're not that good a shot," said Wobbler. "You got kicked out of the Paintball Club, didn't you?"

"Only `cos they were jealous that they hadn't thought of a paintball hand grenade before I showed them how."

"It was a tin of paint, Bigmac. A two-litre tin."

"Well, yeah, but in contex" it was a hand grenade."

"They said you might at least have loosened the lid a bit. Sean Stevens needed stitches."

"I didn't mean actually shooting your actual grandfather," said Yoless, loudly. "I mean messing things up so maybe you're not actually born or your time machine never gets invented. Like in that film where the robot is sent back to kill the mother of the boy who's going to beat the robots when he grows up."

"Good one, that," said Bigmac, strafing the silent shops with an invisible machine gun.

"But if he never got born how did they know he'd existed?" said Yoless. "Didn't make any sense to me."

"How come you're such an expert?" said Wobbler.

"Well, I've got three shelves of Star Trek videos," said Yoless.

"Anorak alert!"

"Nerd!"

"Trainspotter!"

"Anyway," said Yoless, "if you changed things, maybe you'd end up not going back in time, and there you would be, back in time, I mean, except you never went in the first place, so you wouldn't be able to come back on account of not having gone. Or, even if you could get back, you'd get back to another time, like a sort of parallel dimension, because if the thing you changed hadn't happened then you wouldn't have gone, so you could only come back to somewhere you never went. And there you'd be - stuck."

They tried to work this out.

"Huh, you'd have to be mad even to understand time travel," said Wobbler eventually.

"Job opportunity for you there, Johnny," said Bigmac.

"Bigmac," said Yoless, in a warning voice.

"It's all right," said Johnny. "The doctor said I just worry about things too much."

"What kind of loony tests did you have?" said Bigmac. "Big needles and electric shocks and that?"

"No, Bigmac," sighed Johnny. "They don't do that. They just ask you questions."

"What, like "are you a loony?"

"It's be sound to go a long way back in time," said Wobbler. "Back to the dinosaurs. No chance of killing your grandad then, unless he's really old. Dinosaurs'd be all right."

"Great!" said Bigmac. "Then I could wipe `em out with my plasma rifle! Oh, yes!"

"Yeah," said Wobbler, rolling his eyes. "That'd explain a lot. Why did the dinosaurs die out sixty-five million years ago? Because Bigmac couldn't get there any earlier."

"But you haven't got a plasma rifle," said Johnny.

"If Wobbler can have a time machine, then I can have a plasma rifle."

"Oh, all right."

"And a rocket launcher."

A time machine, thought Johnny. That would be something. You could get your life exactly as you wanted it. If something nasty turned up, you could just go back and make sure that it didn't. You could go wherever you wanted and nothing bad would ever have to happen.

Around him, the boys" conversation, as their conversations did, took on its own peculiar style.

"Anyway, no-one's proved the dinosaurs did die out."

"Oh, yeah, right, sure, they're still around, are they?"

"I mean p'raps they only come out at night, or are camouflaged or something... "

"A brick-finished stegosaurus? A bright red Number 9 brontosaurus?"

"Hey, neat idea. They'd go round pretending to be a bus, right, and people could get on - but they wouldn't get off again. Oooo-Eee-Oooo ... "

"Nah. False noses. False noses and beards. Then just

when people aren't expecting it - UNK! Nothing on the pavement but a pair of shoes and a really big bloke in a mac, shuffling away ... "

Paradise Street, thought Johnny. Paradise Street was on his mind a lot, these days. Especially at night.

I bet if you asked the people there if time travel was a good idea they'd say yes. I mean, no one knows what happened to the dinosaurs, but we know what happened to Paradise Street.

I wish I could go back to Paradise Street.

Something hissed.

They looked around. There was an alleyway between the charity clothes shop and the video library. The hissing came from there, except now it had changed into a snarl.

It wasn't at all pleasant. It went right into his ears and right through Johnny's modern brain and right down into the memories built into his very bones. When an early ape had cautiously got down out of its tree and wobbled awkwardly along the ground, trying out this new "standing upright" idea all the younger apes were talking about, this was exactly the kind of snarl it hated to hear.

It said to every muscle in the body: run away and climb something. And possibly throw down some coconuts, too.

"There's something in the alley," said Wobbler, looking around in case there were any trees handy.

"A werewolf?" said Bigmac.

Wobbler stopped. "Why should it be a werewolf?" he said.

"I saw this film, Curse of the Revenge of the Werewolf," said Bigmac, "and someone heard a snarl like that and went into a dark alley, and next thing, he was lying there with all his special effects spilling out on the pavement."

"Huh," quavered Wobbler. "There's no such things as werewolves."

"You go and tell it, then."

Johnny stepped forward.

There was a shopping trolley lying on its side just inside the alley, but that wasn't unusual. Herds of shopping trolleys roamed the streets of Blackbury. While he'd never seen one actually moving, he sometimes suspected that they trundled off as soon as his back was turned.

Bulging carrier bags and black plastic dustbin liners lay around it, and there was a number of jars. One of them had broken open, and there was a smell of vinegar.

One of the bundles was wearing trainers.

You didn't see that very often.

A terrible monster pulled itself over the top of the trolley and spat at Johnny.