And then suddenly it all went wrong. The man in the suit was half jumping, half falling from the stool, and the noose could not have been secured to the ceiling because although it was around his neck it didn’t stop him falling from the stool and then the camera was dropped and there was nothing to see and only the sounds of a furious struggle and the soft thud of punches thrown into flesh and bone and the weeping of a man who was suddenly aware that there was no escape.

As the camera was picked up, I saw some dark figures taking their places against a wall, standing like masked sentries under a single 8 x 10 inch photograph that had been attached to the wall of a smiling boy, perhaps eleven years old, wearing school uniform as he posed happily for the photographer.

I looked at the boy’s smile and I knew with total certainty that the man being forced onto the back of the stool had somehow killed him.

‘Do you know why you’ve been brought to this place of execution?’

Someone was kicking at the stool. The man flapped his arms and I saw that his hands were not tied. But the noose was still around his neck and now it was secured to the ceiling.

‘There’s four of them,’ John Caine said. ‘At least. Four that I can see. Black tracksuits – I think I saw a Nike logo. They’re all wearing tactical Nomex face masks – that’s what those masks are. The one who held the camera is the one who did the heavy lifting when the victim tried to do a bunk. A very big geezer. Can’t see much of the others.’

The man on the hanging stool screamed once.

‘No!’

‘But who is he?’ John Caine said. ‘And who’s the kid?’

The man in the suit hung.

With his hands unbound, he fought against the rope tightening around his neck more fiercely than Mahmud Irani had fought it, he clawed at his neck, he ripped and tore at it, he lashed wildly with his legs and he tried to scream in protest, although no sound was possible other than the terrible noise that a man makes when he is being strangled to death. But he fought more fiercely and so it was over more quickly.

The man stopped kicking. The screen froze, one spot of fresh blood on the eye of the lens.

‘Why don’t they just stab him in the eye?’ I said, getting out my mobile phone.

‘Because that would look like murder,’ John Caine said. ‘And – I’m just guessing here – they think that murder is too good for him.’

I watched the digital world react.

#bring it back

#bring it back

#bring it back

#bring it back

#bring it back

‘You want me to drive you to West End Central?’ John Caine said.

‘Thanks,’ I said. ‘But it’s faster to run.’