She read through the CIA’s version of Knox’s service record. It turned out the agency had noted the closeness between him and his fellow agent and friend, even speculating after Williams’s presumed death that Knox might not recover from the loss. Then she read about the agency’s assessment of the time he’d spent as MI5’s grand inquisitor at the start of the decade, endlessly hunting moles and under­mining Service morale until he’d finally been proved right.

She lingered over the official write-up of the mission that had brought the two of them together, relishing the grudging praise that had been handed to her as the CIA ‘member of staff’ who had helped secure the defection of a key Soviet scientist, and blown the cover of a KGB asset working inside MI5.

The last five years of information was more patchy. With most of Knox’s time spent travelling the Commonwealth dealing with old colonial problems, he’d fallen a little off London station’s radar. What scraps of information there were about him seemed to describe a different person to the man Bennett knew—a man who did what he was told, avoided rocking boats, and was apparently no longer terrified of flying.

Bennett slipped Knox’s files back into their drawer as she heard Eloise’s footsteps returning. She didn’t want to give away more clues about the less than heroic mission that had brought her down into the archive. But Eloise didn’t ask her what she’d been doing while she was gone, or why she wanted the files she’d fetched. She just quietly handed them over and waited for Bennett to read them.

It took Bennett ten minutes to scour the reports Eloise had collected. They covered agent extractions gone wrong, the deaths and disappearances of politicians and businessmen all over Europe, and a lot of questions that had been left unanswered. Some of these questions seemed conspicuously large to Bennett, others almost too small to notice. There was the Italian tycoon’s yacht that had inexplicably sunk in the middle of the Mediterranean, the CIA informant gunned down on the wrong side of the Berlin Wall, the three Turkish nationalist generals who died mere weeks apart, one of a heart attack, one of an aggressive cancer, and one during a live fire exercise.

Like so much to do with the Wolf, there was no discernible pattern that connected them. But if they weren’t random, the only thing that could explain them was a highly trained operative working to some secret agenda who was extremely good at covering their tracks.

Bennett was impressed by Eloise. Sometimes accidents did happen, and coincidences were often exactly that, but the file clerk had a gift for spotting the not quite right. Bennett almost took another gamble and asked her if she was a fellow believer, but stopped herself.