In The Element of Crime, a British detective named Fisher (Michael Elphick), who has become an expatriate living in Cairo, undergoes hypnosis in order to recall his last case. The Europe of his dreamlike recollection is a dystopia, dark and decaying. Fisher remembers pursuing an elusive killer called the "Lotto Murderer", who was strangling and then mutilating young girls who were selling lottery tickets. He attempts to track down the killer using the controversial methods outlined in a book entitled The Element of Crime, written by his disgraced mentor, Osborne (Esmond Knight). He is joined in his search by a prostitute named Kim (Me Me Lai), who, it turns out, has had a child by his target. Fisher's search is based on a tailing report written by Osborne when trying to track down a murderer who had been killing in the same way as the "Lotto Murderer", but who, supposedly, has since died in a crash. The Osborne method requires the detective to try to identify with the mind of the killer. This he does, but, in so doing, begins to behave more and more like a serial killer himself.