Tennant called Gabriel.

‘Sophie – we’re letting the crowd out of the stadium, but encouraging as many to stay,’ he said. ‘Nothing else is practical right now – without the risk of the poor sods getting trampled in the panic.’

‘I have to say I’m uneasy about this, sir. We’ve still got three cell members unaccounted for and armed with semis.’

‘I know. But there’s no alternative. What’s happening at the flat?’

‘We’re evacuating, sir, and containing residents in the street. If the drone is returning here, Abu Mujahid may choose to sterilise the crime scene.’

#

Stonebridge, North West London

Campbell had pulled up on the road outside the Islamic Centre, opposite the flats. The street had been closed off at both ends and the first residents were tumbling, scared and bewildered, onto the pavement.

At first, Campbell could barely make out the sound of the drone over the police helicopters and rumble of traffic on the North Circular. But within seconds, its distinctive high-pitched whirring was audible to all those outside the flat.

‘Keep them moving back,’ shouted Campbell to the constables controlling the residents. ‘Get back as far as you can – get on the road. Get as far away as you can.’

The residents of the flats huddled together. They’d been joined by occupants of the neighbouring block.

The whirring grew louder – and the drone appeared at the top of the block of flats. It hovered for a moment, then descended, as if it was being let down on a fishing wire. It went out of sight behind the building and the noise began to quieten down.

#

Inside Gladstone’s flat, Abu Mujahid listened as the drone’s blades came to a stop. He felt for the grey relay box again. What he needed was a distraction while he got out of here and maybe a last V-sign to the police. His thumb found the switch. He shielded his face with the crook of his elbow, crouched behind the wall and pressed the switch.

For a second, he wondered if the relay box had broken, or if its radio signal – like the signal from the drone controller – was also too weak to get through the walls and floors of the flat. But then came a tremendous boom, which echoed off the buildings and walls around him. A man outside shouted; a toddler cried.

Calmly, slowly and with the arrogance of victory, Abu Mujahid slid open the kitchen window, thrust his hand through the visor of the motorcycle helmet so he could carry it on his arm and keep his hands free, slithered out of the flat, crept across the yard and shimmied up the fence, dropping into the street on the other side. His right ankle gave way awkwardly as he fell. He could walk on it, but it hurt badly, he thought, before limping away.

#

Wembley Stadium, North West London

Sulaiman Khan held his son in his arms. All he could think about was the boy slipping and vanishing beneath the crushing, trampling feet around him.