A sub-postmistress is fatally stabbed in a small-scale robbery, and Frost wastes a lot of time questioning the leading suspects. Then, Helen Tudor, a beautiful first-year psychology student and keen swimmer at Denton University, is attacked on the campus, and suspicion initially falls on her psychology tutor, Keith Michaelson, but Frost's investigations uncover a link with the death of another beautiful young girl swimmer two years earlier, in another town.

Frost is held at gunpoint by a drugs dealer, a Territorial soldier is shot dead on an exercise, and a security van is robbed by a shotgun-wielding gang. Frost investigates the three incidents, and tries to find any links between them. His intrusions onto the army base stir up hostility from the commanding officer.

Frost's house is burned down, and he moves in with a colleague temporarily. A mysterious, ruthless kidnapper on a motorcycle tests Frost's skills to the limit. It proves a tough case to crack, and for the abducted woman, time is running out.

A young woman is found viciously stabbed to death. Frost consults the victim's personal organiser, from which a trail leads him to a religious community.

A woman commits suicide naked in public, and Frost connects her death with the later death of a gigolo. He discovers that the dead man had business with several women in Denton. Meanwhile there appears to be a series of break-ins at the local cricket pavilion, and Supt Mullett, who is a member, orders Frost to investigate them as well as the murder.