The next lunchtime Todd and the others took the film to the police station. PC Roberts took them into a back office and they watched it. Todd had been looking forward to it, but he was disappointed when he saw what was on the screen.

‘I had to use night-vision lenses,’ Louise explained.

The picture was dark and had a green tint. It was possible to see the shapes of the wheelie bins and shadows. That was it. Mugger’s Alley looked like a strange planet.

PC Roberts watched carefully. He asked a number of questions. When Dex came onto the screen, panting past the girls, Todd began to feel a little better. Then came Ripley soon after. What happened next was over very quickly. The screen was filled with Ripley’s face. He was holding something in the air but it was hard to see what it was.

Todd groaned to himself. He put his head in his hands. Had it all been for nothing?

‘Well, well!’ PC Roberts said, pressing the STILL button.

Todd looked up. The frozen image showed Stephen Ripley with a baseball bat above his head. His eyes were glowing. He looked like an alien. His face was recognisable. Just.

PC Roberts pushed the PLAY button and the film played on. His thumb pressed the volume and Stephen Ripley’s voice became loud. Louise had set up a remote microphone in one of the bins. It picked up everything that was being said.

‘I’ll just break one of your legs tonight. Then, if your mate doesn’t change his statement, I’ll come back and break the other one tomorrow.’

‘That’s interfering with witnesses,’ Todd said, excitedly.

‘Um …’

PC Roberts didn’t answer. The film played on until the end when Ripley turned around to face the camera. Then he ran off.

‘You can arrest him for that! Can’t you?’ Louise said, looking pleased with herself.

But PC Roberts sat looking thoughtful. His hand strayed up to his forehead and he felt along the line of his scar.

‘Strictly speaking he’s not interfering with witnesses, because Dexter here was not a witness to anything.’

Dex looked uncomfortable. Todd felt angry, suddenly.

‘He beats up Dex and gets away with it!’ he said.

‘No. It’s Threatening Behaviour. Stephen Ripley has done this before a number of times. In the past he’s been let off with community service. I was in court with him a month or so ago and the magistrate said it was his last chance. He’ll get a custodial sentence this time. No doubt.’

They were all quiet for a moment. PC Roberts pressed the rewind button. They watched as the film started moving backwards at speed. The dark green colours of the alley. Ripley’s white overall running backwards past the dark shapes of the wheelie bin. It was another world. Weird.

Todd left the station feeling better than he had for days. Dex was walking ahead with Lindy. There was something different about his friend. He looked taller, or his back was straighter. He was certainly walking fast, his hands swinging at his sides.

The baseball bat had been a nice touch. Todd had thought that Dex took it with him to protect himself. But he had always intended for Ripley to take it off him. I knew it would make the film more dramatic, he’d said.

Louise had taken the video recorders into school that morning and edited the film. She had cut it at various points to make it clearer. It had been shaky and dark. But it had done the trick.

‘You did a great job,’ Todd said to Louise when the others were far ahead.

‘OK. I deserve a kiss then!’ she said.

Todd felt himself go red, but he stopped walking and leant forward to give her a kiss on the lips. Louise looked as though she’d just won a prize.

‘We’d better catch up with the others,’ he said.

Later the four of them stopped outside Wilson’s Food and Wines. The shutters were down and there was a notice pinned on the door.

We are closed due to the sad loss of George Wilson. Many thanks for the flowers and sympathy.

Louise was holding a bunch of carnations that they’d bought at the supermarket. She placed it on the pavement in front of the shop. They all stood quietly for a minute.

Then they walked back towards school. Todd looked at his watch. With a bit of luck he wouldn’t be late. For once.