Murphy's Law

To find out where a kidnapper has hidden one of his victims, Murphy goes undercover as an inmate in the kidnapper's prison.

Murphy and Guthrie are assigned to protect a famous snooker player.

DS Murphy is working undercover when a member of his "gang" and a mate from school days, Peter Tate, is shot on the street. The dead man's brother, Carl, is out for revenge and the police fear a gang war. Murphy manages to calm them somewhat but Carl is convinced that his brother's is a revenge killing by the Tyler family and sets out to get even. Annie Guthrie eventually joins Murphy undercover in an attempt to get closer to Carl.

After 5 months undercover, Murphy finds himself looking over his shoulder when the arms dealer he had befriended, Nikolai, gets away. He subsequently ransacks Murphy's apartment looking for revenge. The police now investigate two very similar deaths. Both victims were male, quite rich and were at the same health club the day they were killed.