‘Abu Mujahid.’ It wasn’t a question. What better way to tidy up a crime scene than detonate an explosive?

For a giddying moment, Gabriel imagined him standing in the crowds outside Wembley, gun in hand, aiming at the oncoming crowds. But she shoved away the thought. That wasn’t his style. He wasn’t one for martyrdom. So where was he? A memory leapt out of the darkest corner of her head. Something she’d seen when the CTSFO team swept through the flat earlier.

Bose, who was listening in, seemed to have sensed her initial anxiety.

‘Shall I get on to Gold, ma’am, and warn them that he could be heading for Wembley?’ She looked up almost eagerly for approval.

‘Come on, Eva, use your head,’ Gabriel said. ‘He’s a coward. He sets up others to die for the great cause and he has no interest in being a martyr. He has an escape plan, and he’s had it since before he moved back to London. Pull up the video of the CTSFOs raiding Abu Mujahid’s flat,’ she called out to one of the duty DCs in the ops room. ‘Start when they were in the hallway.’

Moments later, the shaking image of the bodycam of the lead CTSFO filled the main screen. The image swayed and spun as the officer began the careful yet urgent sweep of the flat, room by room, wall by wall.

Bose came over to stand next to Gabriel, who was sat at a desk, her sharp elbows on the surface, her hands clamped around her cheeks and her eyes bright and alert.

‘What are you hoping to see, ma’am?’ asked Bose.

‘If I knew, I wouldn’t need to watch this again.’

Gabriel continued to focus on the screen. The camera was now in the hallway, approaching the cupboard where Tanvir Mirza’s body had been dumped. A gloved hand opened the door, and the camera hovered over the fold of grey plastic taped tightly around Mirza’s body. Another person robbed of life by Abu Mujahid, another disposable corpse to add to his collection, thought Gabriel. Had Mirza’s parents been told yet, she wondered. Did they know that their beloved son, the young man they had been so worried about, had been involved in this – and was now lying wrapped in plastic bin bags like a piece of household waste?

The camera moved around the cupboard to an ironing board, and across shelves of washing powder and cleaning products.

‘What’s that?’ Gabriel said. ‘Go back and freeze it.’

The video paused and rewound, freezing again on an empty white cardboard box, its top ripped off, its contents removed. The writing was illegible, but the image on the packaging was clear. A red motorbike helmet with visor.

Gabriel’s eyes glittered. ‘That’s it,’ said Gabriel. ‘That’s Abu Mujahid’s.’

‘How can you be sure?’ said Bose.

‘Because Abu Mujahid’s life history is locked away in here, Eva.’ She tapped her forehead. ‘When he was a teenager, when he was still just plain Jack Pearce, he was nicked for stealing mopeds. And he had his own bike until he went to prison first time round. A blue Honda. I could even tell you its registration number, if you like. That’s his helmet. And that means he had a bike nearby. Think about it, Eva, what better way for him to get away from the flat, anonymously? Get CCTV now – close to the flat, and covering the fifteen minutes after the drone exploded. Double-check with the flat owner – see if she had a helmet in the cupboard. But I bet she didn’t. And get the CCTV team searching the streets – get them to look in the fifteen-minute window after the drone exploded at the flat.’