DI Chappel has to sacrifice his new relationship to save Sgt Robinson from the murder accusation.

The Vice Squad investigates the murder of a pimp. Sgt Robinson comes under suspicion for the murder. DI Chappel begins a relationship with the victim's mother.

Desperate to crack the Eastern European sex-slave ring, DI Chappel betrays an old friend, with deadly consequences.

The Vice Squad investigates a massage parlour where Eastern European girls are being forced to work as prostitutes after being illegally smuggled into the country. Sgt Robinson's marriage gets emotionally involved with a witness.

Chappel's efforts to bring down the illicit gambling and prostitution organisation pushes PC Raymond to the brink.

DI Chappel and PC Hutchins work undercover to investigate the gambling operation at The Jupiter nightclub.

DI Chappel and Sgt Robinson uncovr a London pimp's connection to the children's home where he recruits child prostitutes. Chappel seeks comfort in the bed of a colleague.

DI Chappel and Sgt Robinson travel to Sheffield to uncover the reason that young girls from a children's home are becoming prostitutes in London. Chappel offers a roof to PC Hutchins.