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.

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.

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.