“I read it!” Lucas could hear Terrence scrambling to obey, for all that it was probably too late.

“Not past the first fucking page, you didn’t.” There’d been a photo of a young Khan there, from when he was with some government think tank or other: a slight, unassuming Indian guy, glasses, moustache. Of course, three pages in there were more current photos that showed him in a very different light, but apparently Terrence hadn’t felt that reading the brief was a priority. All eagerness, no diligence. Lucas was going to take pleasure in shopping the bastard to Rove’s HR people, but only once they had their mark. If they didn’t get that, he suspected he wouldn’t be taking much pleasure in anything.

For a moment he thought they’d lost their chance. The dots exploded outwards, fizzing across the screen as though Pryor and Khan were dust that might end up anywhere from here to Azerbaijan. Then everything was coalescing towards Crowne Plaza. He wondered if they had left something in that crappy hotel, or were maybe trying to get to King’s Cross Station. He dropped a request to the office for someone to watch the trains, just in case.

“I see them.” Terrence sounded out of breath on the phone. “I’ve got them, I’m going to—”

“Fucking watch and wait and don’t do anything suspicious.” Lucas broke into a run. “Everyone converge on his position. Get ahead of them. Where are they going?”

“Sir, I can—”

“You will not,” Lucas said, because one criminally over-enthusiastic agent trying to capture two people was never going to work out. Even ignoring the possibility that either might be able to call on something unnatural at a moment’s notice.

“Sir,” said Terrence in a mutinous tone, “they’re heading to a Post Office.”

“The fuck?” Lucas demanded. He scrolled his phone map as best he could. “Is that…Mount Pleasant?” His map was showing a huge postal sorting centre taking up a city block. “Terrence, what’s that in the background?” Not just interference: a high-pitched, irregular sound.

“There’s a load of people out on the street,” Terrence said. “I think our targets are trying to lose themselves—no, wait, they’re going round them.”

“What am I hearing?” Louder now, past Terrence’s breathing and the murmur of second-hand traffic.

“Fire alarm,” Terrence said.

Josef added, “I see them too.”

Amin was two streets away, lagging behind Lucas. Lucas had the police ID, though: if they were going to make it look like an arrest, he’d rather lead it. “Amin, go back, bring the car up.” Not that it had helped last time, but he wanted their quarry off the streets and somewhere secure, preferably with a gun shoved discreetly into someone’s ribs, as soon as possible.

“They’ve gone into the Post Office’s vehicle yard,” Josef said. “Heading for the main building. Pursue?”