Lines from an unknown poem are the trademark of a brutal killer who is preying on a wealthy group of Americans visiting Stratford and bedeviling the investigation of Scotland Yard's Superintendent Richard Jury.

While sitting in a London pub Richard Jury hears a story told by Harry Johnson about the disappearance of a good friend's wife and son (and dog). The vanished woman's husband excels in the esoteric subject of quantum mechanics, could this explain the disappearance? The dog did come back but how and from where?

Jury investigates the death of a young escort who has been murdered behind a local pub. The only witness is the establishment's black cat, who gives neither crook nor clue as to the girl's identity or her killer's.

"In the latest series outing, The Knowledge, the Scotland Yard detective nearly meets his match in a Baker Street Irregulars-like gang of kids and a homicide case that reaches into east Africa. Robbie Parsons is one of London's finest, a black cab driver who knows every street, every theater, every landmark in the city by heart. In his backseat is a man with a gun in his hand--a man who brazenly committed a crime in front of the Artemis Club, a rarefied...