There followed a tense conversation between Taylor and the chief of the intelligence service, Sir Roland Mackenzie. Mackenzie had taken on the role of “C” four years ago, and while he was an imposing figure, Taylor got a sense that he supported her; beneath the old-school exterior he was a modernizer who had personally intervened to ensure Taylor’s professional rehabilitation after her incident. When Ventriloquist came up, he trusted her with the project—and their shared knowledge of the scheme had created a bond.

“The Yard aren’t stupid,” Mackenzie said. “They know this is intelligence related. The important thing is we manage the reach of their inquiry.”

“I agree.”

“Have a cover story ready, something else he might have been over there for. Something that, in a worst-case scenario, isn’t going to blow ongoing operations if it leaks. Don’t give them that unless you absolutely have to—use whatever tactics you can. But you tell them nothing that touches on Echelon. That is a red line.”

A couple of hours later she was sitting in a cramped office belonging to Homicide and Major Crime Command. Opposite Taylor was Detective Chief Inspector Aisha Rehman, who had taken an interest in the case. Rehman was young for a DCI, suggesting aptitude, with short dark hair and the unblinking stare that Taylor had noticed in every good detective she’d met. Beside her was another inspector with graying sideburns who rolled a pencil between his finger and thumb. From the look in their eyes it was clear that when they’d smelled MI6, they’d prepared for battle.

Rehman opened a file of photos: Petra smiling, Petra as Miss Ascension, a map of the island. She spread the images as if to say: This is real. Not spook stuff. This is why police have priority over spies. Although it was never quite that simple, which was why Taylor had received C’s warning, and why she had arrived at the Yard accompanied by a lawyer for the intelligence service and a GCHQ security officer on the lookout for potential indiscretions. Both were rigidly suited, bristling with their assigned duties.

The working relationship between the police and intelligence service was fraught at the best of times. The intelligence service didn’t investigate or prosecute crime; only the police did. But MI6 got itself involved in it—exploiting it, investigating it, using it for concealment—and the police entered with the law’s demand for knowledge before invariably hitting a wall of silence. To the intelligence service, secrecy meant security; to the police, it indicated guilt. This created conflict. And when police were occasionally tasked with investigating MI6 itself—as it had done over torture allegations—it didn’t build any bridges.