She ended the call and dropped the phone back into the postbag. She left the flap open and rain patted in among the letters as she began to walk. After a few strides an involuntary spasm ran through her and she started to jog. She ran away from the main shopping area and headed towards the seafront, her feet moving faster. Trotting, running, sprinting. At some point she lurched to a stop and looked down at the bag. Everything inside was sodden. She dropped the bag onto the pavement and removed her waterproof coat. The red and blue. The uniform. She folded the coat neatly and placed it on the pavement and ran up to the expanse of grass that overlooked Plymouth Sound. Out to sea, sheets of rain swept across the water, lashing down on a solitary grey warship moored in the centre of the bay. For a second a shaft of brightness shimmied across the sea but then it was gone as dark clouds rolled in from the west. Silva ran across to a nearby bench and slumped down, breathless, on the wet surface. She pulled her knees up to her chest and rocked herself back and forth as the rain continued to fall, not wanting to stop moving, not wanting to think.

Holm found a clean shirt but his suit lay crumpled where he’d thrown it when he’d arrived back from work. He pulled on the trousers and jacket and grabbed a couple of chocolate biscuits from a cupboard in the kitchen. A swig of milk straight from the carton in the fridge and his breakfast – at four fifteen in the afternoon – was done.

Half an hour later he was emerging from the depths of Victoria tube station and striding towards the river. He headed up Millbank, dodging people coming the other way. It was rush hour now and most folk were going home. Throngs of workers. Crowded buses. Nose-to-tail traffic. As Holm neared Thames House, he looked across at a couple of young mums with babies strapped to their fronts. Nearby a trio of city types shared office banter and a teacher led a group of foreign schoolchildren on a tour. This was the soft underbelly of the country, awash with easy targets. Many a time he’d discussed with colleagues how lucky they were that most terrorists were fairly stupid. How else to account for the relatively low number of attacks? Sure, the security services had had great success in foiling a number of plots, but it didn’t explain why there weren’t more.

At Thames House he went through the rigmarole of passing through security and made his way to the situation room. When he’d left in the early hours there’d been empty chairs and blank monitors, but now every screen was ablaze and nearly every chair taken. People talked into phones, fingers clattered across keyboards and a buzz of half a dozen different languages filled the air.