Trial & Retribution

A five-year-old girl goes missing and the police are called in to search. When her body is found inside a sewage pipe, it becomes a murder investigation, which is headed by Detective Superintendent Walker. They follow a few leads and eventually arrest a suspect, who is then sent to trial.

When Susan Harrow does not come home, her mother reports her missing to the police. Her body is later discovered on waste land and a murder investigation is launched, once again headed by Det. Supt. Walker. There is later a second murder and they know that they have a serial killer on their hands.

A fifteen year old girl goes missing and her blood-stained clothes are found. Det. Supt. Walker heads the investigation into her murder. Meanwhile, D.I. North is sent to see a persistent complainer, Warrington, who has been hounding the station. North begins to get stalked and Walker has a prime suspect for the murder. But then they find a connection between Warrington and Walker's prime suspect.

D.I. North re-investigates an eight-year-old murder case and finds that Det. Supt. Walker was in charge of the inquiry. She begins to suspect that he's covering something up and he is suspended from duty. He returns to his roots to find new evidence to prove his innocence, in order to save his career, relationship and reputation.

Walker is assigned to investigate the discovery of a 17-year-old skeleton, which he isn't too happy about - especially as he's working with D.I. North's ex-boyfriend. They soon discover more skeletons buried at the house.

D.I. North investigates when a girl is snatched from a wood, but the confession of a local sex offender complicates matters. Detective Chief Superintendent Walker is little help, as he has worries of his own.

A severed female hand is found in the Thames, which brings D.C.I. Conner in contact with Walker (who is now back in uniform). No body is discovered, and the case soon becomes a battle of wits against the killer.

A young prostitute, Angela Dutton, plunges to her death from the eleventh floor balcony of a block of flats. The police begin a murder enquiry and discover that she was the daughter of a seventies TV star who was also found murdered twelve years earlier, wrapped in blue eiderdown. The killer was never found. D.C.S. Walker heads the investigation into the two murders, with the aid of D.C.I. Connor and the rest of the team. They investigate to find out why Angela Dutton died - did she find her mother's killer, or did one of her three high-paying clients kill her?

The apparently happy Harrogate family is torn apart when they return home to discover their daughter, Emily, dead. Connor and Satchell begin to sift through the case and discover that the family isn't as stable as it first appeared. Connor appeals to Walker for some backup, who is having problems of his own with his own son Richard. Secrets are soon discovered and fragile relationships are tested in the process of ensuring justice is done.

A suitcase is found abandoned at Heathrow Airport, and panic ensues, but it is soon discovered to be no terrorist threat. Inside is the naked body of Sofia Petrenko, a high-class prostitute, who has been strangled to death. The suitcase is traced to Vitali Malikov, a Ukrainian billionaire who admits to hiring Sofia's services, but he claims she was alive when she left him and that the case was a gift. D.C.S. Walker arrests Malikov on suspicion of murder, but later has to release him, and soon realises he has become a pawn in a much bigger game.

An ambulance is forced off the road as it is carrying a famous patient in the back. The patient is then shot in the head.