A young school girl is raped and murdered, but D.C.I. Connor still has no leads a month into the investigation. When Walker orders a review of unsolved cases, they turn up similar cases of raped and murdered teenage girls over the last ten years, and they find themselves searching for an apparent serial killer.

A young school girl is raped and murdered, but D.C.I. Connor still has no leads a month into the investigation. When Walker orders a review of unsolved cases, they turn up similar cases of raped and murdered teenage girls over the last ten years, and they find themselves searching for an apparent serial killer.