‘Where?’

‘It was about a kilometre to the east of the flat. It was hovering over waste ground near a railway. Hard to spot when it’s not moving. But it’s now travelling back south.’

‘Not towards Wembley?’ said Tennant.

‘No, sir. Seems to be flying at full speed south.’

‘Sir.’ It was Amanda Elliott, the drone expert. ‘I’ve had a thought – and not a pleasant one. Consumer drones like this tend to come with a fail-safe. If they are under manual remote control and the signal fails, or if the battery is running low, they automatically return to their base – the launch point – for safety.’

Tennant froze. ‘Are you sure?’

‘Not sure, sir, but it’s a very real possibility that the drone – carrying its explosives – might be heading back to the block of flats.’

‘Oh, Jesus. Get the entire building evacuated now. How long?’

‘They’ve got about two minutes, I reckon, sir,’ said Elliott.

#

Stonebridge, North West London

The rising and falling wail was overwhelming and seemed to emanate from within Abu Mujahid’s head. It took a second for him to realise what it was. The fire alarm. They were evacuating the building.

In the old woman’s bedroom that smelled of lavender and talcum powder, he grabbed a sheet from the bed and pulled it to the sitting room, laying it out on a rug on the floor.

He picked up the old woman’s frail body and placed it on the sheet, then wrapped the sheet and rug around her. He found it easy to carry the body – she must have weighed less than eight stone – to the bathroom and drop it in the bath. The bathroom door had a lock that could be opened from the outside with a screwdriver. He dived into a kitchen drawer and pulled out a knife. That would do. He locked the bathroom from the outside and returned to the kitchen to wash his hands and face. It wouldn’t take anyone long to knock down the bathroom door and find the body, but those extra seconds could be the difference between life and death for him. He was wearing an anorak over his jacket, so pulled the hood over his face and put on a pair of dark glasses. He felt inside the jacket pocket for the relay box – and his handgun – and stood by the kitchen window.

#

Special Operations Room, Lambeth, London

The new injury estimates were better than Tennant could have hoped for. Two serious injuries now, twenty-five walking wounded, no fatalities. But the spectators were building up at the turnstiles. The commander on the ground at Wembley sent through a request to open the doors.

The Gold Commander swore. ‘If they’re in the stadium, at least they’re within the security cordon. Let them out and we have no control over their safety.’

‘I accept that, sir, but there’s a serious risk of crushing.’

The Gold Commander cursed again and gave the order to evacuate the stadium.