On a wintry night in December 1985, 19-year-old Alison Day goes missing after getting off a train - and her disappearance turns into a murder hunt when her body is recovered from a canal.
Police are desperately trying to find the two men responsible for the sadistic murders of Maartje Tamboezer and Alison Day, before the killers have a chance to strike again.
John Duffy has been sentenced to life for murder and rape. But he wasn't alone in these crimes, and after almost a decade of silence, he starts to talk.
