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.
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.
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.
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.
Murphy is out posing as a criminal armourer to make an arrest. During the set-up he recognises Caz Miller, a man known for his connections to criminal gang leader and known cop-killer Dave Callard. Miller tells Murphy that he wants to kill another gang member called Richard Holloway. Murphy stops the planned arrest because he thinks he can gain Callard's trust and infiltrate the entire criminal organisation to take everyone out.
After months spent trying to nail gangster Dave Callard, suddenly Murphy has a bigger fish to fry: a wealthy hotelier called George Garvey with a taste for ethnic art. Murphy bumps into someone to whom Garvey's son owes a lot of money and manages to get closer to Garvey. To forget the pressure during work he starts to drink. It looks like only Ellie can save him now.
Now that Baker knows Murphy is a cop, he must race against the clock to find Kim before her secret is revealed too. However, local Chief Superintendent Bowry cares less about Kim's life and more about his own reputation and funding, and Murphy is forced to take desperate measures in his hunt for his missing friend.