He stood up and started to put Bigmac’s labelled belongings into a sack.

‘Hey, that’s my stuff—’ mumbled Bigmac.

‘Lock him up.’

‘You can’t lock me up just for some old car—’

‘We can for spying,’ said Captain Harris. ‘Oh, yes, we can.’

He strode out of the room.

‘Spying?’ said Bigmac. ‘Me?’

‘Are you one of them Hitler Youths?’ said the sergeant, conversationally. ‘I saw you lot on the newsreel. Waving all them torches. Nasty pieces of work, I thought. Like Boy Scouts gone bad.’

‘I haven’t spied for anyone!’ shouted Bigmac. ‘I don’t know how to spy! I don’t even like Germany! My brother got sent home from Munich for stitching up one of their football supporters with a scaffolding pole even though it wasn’t his fault!’

Such rock-solid evidence of anti-Germanic feeling did not seem to impress the sergeant.

‘You can get shot, you know,’ he said. ‘For the first offence.’

The door was still open. Bigmac could hear noises in the corridor. Someone was talking on the phone, somewhere in the distance.

Bigmac wasn’t an athlete. If there was an Olympic Sick Note event, he would have been in the British team. He would’ve won the 100 metres I’ve Got Asthma, the half-marathon Lurk in the Changing Rooms, and the freestyle Got to Go to the Doctor.

But his boots dug into the floor and he rose out of his chair like a missile going off. His feet barely touched the table top. He went past the policeman’s shoulder with his legs already making running motions. Fear gave him superhuman acceleration. Ms Partridge might make cutting remarks but she wasn’t allowed to use bullets however much she wanted to.

Bigmac landed in the doorway, turned at random, put his head down and charged. It was a hard head. It hit someone around belt level. There was a shout and a crash.

He saw another gap and headed for it. There was another crash, and the sound of a telephone smashing on the floor. Someone yelled at him to halt or they’d fire.

Bigmac didn’t stop to find out what’d happened. He just hoped that a pair of 1990s Doc Martens that had been practically bought legally by his brother off a man with a lorry full of them were much better for dodging and running than huge police boots.

Whoever had been shouting stop or they’d fire … fired.

There was a crack and a clang somewhere ahead of Bigmac, but he turned down a corridor, ran under the outstretched arms of another policeman, and out into a yard.

A policeman was standing next to a Jurassic bicycle, a huge machine that looked as if it were made of drainpipes welded together.

Bigmac went past him in a blur, grabbed the handlebars, swung onto the saddle and rammed his feet onto the pedals.

‘Ere; what’re you doin’—’

The policeman’s voice faded behind him.

The bike swung out into the lane behind the station.

It was a cobbled street. The saddle was solid leather. Bigmac’s trousers were very thin.