‘I don’t want to be history!’ moaned Wobbler.

‘All right, you win,’ said Kirsty. ‘What do you want us to do?’

Johnny shuffled the papers.

‘Well … what I found out for my project was that … there was a big storm, you see. The weather got very bad. And the bombers must’ve seen Blackbury and dropped their bombs anyway and turned around. That used to happen. There was … there is an air-raid siren. It was supposed to go off if bombers were near,’ he said. ‘Only it didn’t.’

‘Why not?’

The folder shut with a snap.

‘Let’s start by finding out,’ said Johnny.

It was on a pole on the roof in the High Street. It didn’t look very big.

‘That’s all it is?’ said Yo-less. ‘Looks like a giant yo-yo.’

‘That’s an air-raid siren all right,’ said Kirsty. ‘I saw a picture in a book.’

‘How d’they work? Set off by radar or something?’

‘I’m sure that’s not been invented yet,’ said Johnny.

‘Well, how then?’

‘Maybe there’s a switch somewhere?’

‘It’d be somewhere safe, then,’ said Yo-less. ‘Somewhere where people wouldn’t be able to set it off for a laugh.’

Their joint gaze travelled down the pole, across the roof, down the wall, past the blue lamp, and stopped when it met the words: ‘Police Station’.

‘Oh, dear,’ said Yo-less.

They sat down on a bench by a civic flowerbed, opposite the door. A policeman came out and stood in the sunshine, watching them back.

‘It’s a good job we left Bigmac to guard the trolley,’ said Yo-less.

‘Yes,’ said Johnny. ‘He’s always been allergic to policemen.’

Kirsty sighed. ‘Honestly, you boys haven’t got a clue.’

She stood up, crossed the road and began to talk to the policeman. They could hear the conversation. It went like this:

‘Excuse me, officer—’

He gave her a friendly smile.

‘Yes, little lady? Out in your mum’s clothes, are you?’

Kirsty’s eyes narrowed.

‘Oh, dear,’ said Johnny, under his breath.

‘What’s the matter?’ said Yo-less.

‘Well, you know you and “Sambo”? That’s Kirsty and words like “little lady”.’

‘I was just wondering’, said the little lady, through clenched teeth, ‘how that big siren works.’

‘Oh, I shouldn’t worry your head about that, love,’ said the policeman. ‘It’s very complicated. You wouldn’t understand.’

‘Look for something to hide behind,’ said Johnny. ‘Like another planet.’

Then his mouth dropped open as Kirsty won a medal.

‘It’s just that I get so worried,’ she said, and managed a simper, or what she probably thought was a simper. ‘I’m sure Mr Hitler’s bombers are going to come one night and the siren won’t go off. I can’t get to sleep for worrying!’

The policeman laid a hand on the shoulder of the girl who had left Blackbury Karate Club because no boy would dare come within two metres of her.

‘Oh, we can’t have that, love,’ he said. He pointed. ‘See up there on Blackdown? Well, Mr Hodder and his very brave men are up there every night, keeping a look-out. If any planes come near here tonight he’ll ring the station in a brace of shakes, don’t you worry.’