‘Maybe.’ She glanced through the glass wall to the ops room. Five minutes were up. They should have him by now.

‘Listen, boss, right now he’s not certain we’re on to him. He knows we were at the flat, but that’s all. So assume for a minute that he thinks he’s in the clear. What’s he going to do? He knows that we’ll find his DNA all over the flat and he will assume that it’ll take us more than a few hours to confirm that the DNA belongs to him. That means he’s got a small window to get out of the country. And I know Abu Mujahid. He’s a glory hunter – he wants to bask in the limelight from all this, he wants to be back with his acolytes.’

She looked out again. There was a bustle of activity around one of the terminals. Bose was talking expressively at the DCs.

Tennant was speaking. ‘So assume he’s trying to flee. He’s been here a few weeks, he’s had time to fix up an escape route. He’ll have access to a fake passport. We can rule out a plane, too risky. Same for a boat. Last time, two years ago, he escaped out in a van from Portsmouth? Right?’

‘A lorry taking a consignment of toilet rolls to France, sir,’ said Gabriel.

‘I remember. Headline writers had a field day when that came out. But didn’t he have a backup plan?’

Gabriel paused. Tennant was right. There was something in his file she’d seen during the inquiry into his escape. What was it? She glanced out of the door again. Still no sign of an arrest.

‘Can I call you back later, sir?’ She walked to the door and shouted to Bose over the hubbub. ‘What’s happening?’

Bose rushed over. ‘Sorry, ma’am, just heard from the riders again. They’ve missed him.’

‘What do you mean “missed him”? How the hell could they miss him?’

‘He’s gone off the grid. He was last picked up by ANPR on Marylebone Road near Baker Street six minutes ago heading east. The traffic’s terrible down there, ma’am, hard even for a moped to get through. He should have popped up on ANPR a few hundred yards later near Regent’s Park. But still no sign of him. The riders have swept up and down the road, but nothing. They’re double-checking and searching side roads now.’

Surely not again, thought Gabriel. Surely he hadn’t done it again.

The main screen was showing live CCTV of Marylebone Road. On smaller screens, shots of side roads appeared and disappeared. Dusk was falling and visibility was poor. Somewhere in that grid of white Portland-stone houses and offices, Abu Mujahid was scurrying through the shadows.

The ops room was silent. Street after street appeared on the screen and vanished, but still there was no moped, no figure resembling their killer.

‘Shit, shit, shit,’ said Gabriel under her breath. He must have dumped the moped and be going on foot. So where the hell was he going? She thought back to her conversation with Tennant.