Following a bungled attempt to close down an elaborate Russian crime-ring, Murphy and Annie find themselves embroiled in what appears to be a textbook crime of passion. An unknown blonde is busy murdering London's successful business people. The only common link is that all the victims are members of a state-of-the-art health club in the heart of the City.

In the glittering world of London’s West End club scene the head of security of a well-known East End gang is found murdered. The prime suspect is another gang leader, Carl Tate. In order to prevent another "door wars", Murphy joins Carl's gang undercover, but when warfare escalates Annie is compelled to join ranks with Murphy on the doors of Carl's latest venture, X-Club.

When Mickey Munday, a world-famous Irish snooker player, comes under pressure to rig the outcome of his game in the forthcoming championships, Murphy and Annie go undercover to protect his life and find the culprit when he arrives in London. The stakes are raised for Munday when his long-lost love and daughter reappear in his life.

Richard Mooney, London's most infamous kidnapper, is brought in, and the race is on for Annie and Murphy to get a confession in time to save the life of his latest victim, Kate Jennings. To crack Mooney’s silence, Murphy is set up as a suspected terrorist and goes under cover into Bellview Prison to befriend him. But when this master plan is unexpectedly threatened by the prison's very own protection racket, time seems to be running out for Kate.

Murphy infiltrates a gang implicated in a series of diamond heists and finds himself out of his depth involving Japan's equivalent of the mafia. Complicating the situation, Murphy finds himself attracted to Annie.