Greene’s fingers flew over his keyboard and the mugshot of Abu Din was replaced by black-and-white footage from a CCTV camera. The camera revealed a crowd of men kneeling in the road of a suburban street. A figure in grey robes stood before them. Abu Din. High above the street I could see the curved arch of Wembley Stadium, glinting in the sunshine at the end of another beautiful day.

‘Abu Din was at the Wembley Central mosque, but they kicked him out after he went on Newsnight and praised the murder of six British soldiers in Afghanistan. So now he preaches in the street.’

I wanted another triple espresso.

‘Abu Din,’ I said. ‘Why does his name seem familiar?’

‘He’s the one they call the Mental Mullah,’ Billy said. ‘I’ll just fast-forward over the prayers, shall I?’ The CCTV footage began speeding up. ‘The papers tagged him the Mental Mullah after he said the killing of British soldiers was “a glorious thing”.’

‘He gets fifty grand a year in benefits for his wife and six kids,’ Edie said. ‘I reckon we must be the mental ones.’

‘The papers had to stop calling him the Mental Mullah because it was considered offensive by mental health charities,’ Billy said. ‘Ah, this is the money shot.’

The CCTV footage slowed down to real time. There were perhaps one hundred men kneeling in the Wembley street. Abu Din himself faced them in his plain grey robes, flanked by what looked like a couple of bodyguards. Both of Abu Din’s index fingers were pointing to the heavens. At the back of the crowd I could see a solitary uniformed policeman, a black officer with the height and bulk of a heavyweight boxer. I guessed he could handle himself. Watching this street wasn’t an easy posting. The uniformed cop was standing directly in front of a young man in a wheelchair. There was a woman behind the wheelchair. Their dark good looks were so similar they could have been twins. The young man was holding up a placard. I could just about make out the words.

My Country – Love It or Leave It.

‘Coming up now,’ Billy said.

The policeman suddenly started to run. The woman gripped the handlebars of the young man in the wheelchair and seemed to hunch, as if expecting a blow. And then the crowd were all getting to their feet, pointing at something out of camera.

They began to scatter.

Running for their lives.

A black transit van was being driven at speed. It appeared to be heading straight for the crowd but suddenly it mounted the pavement to avoid the young man in the wheelchair. I automatically looked for anything that would make the transit van unique. Dents, scratches, words that had been sprayed over. But there was nothing. There was brown duct tape plastered over the registration plate. Simple but effective.