An English musician (David Hemmings) is the only witness to the brutal murder of a psychic medium (Macha Meril). As he takes it upon himself to discover who the serial killer is, he finds that the killer knows his every move as the body count piles up. Directed by giallo maestro Dario Argento, I'd say this was his masterpiece if it weren't for SUSPIRIA. It's a tour de force of visuals, suspense, atmosphere, color, editing, music and style. The killings are more graphic, disturbingly so, than in Argento's previous films. He almost seems to be sadistically relishing our discomfort. The killer's motives are never addressed but I suppose a motive is irrelevant when the killer is "mad". Almost a half hour of footage was cut from the American release by Argento which made the relationship between Hemmings and a journalist played by Daria Nicolodi less coherent and more superficial. That footage has fortunately since been restored. I have to tip my hat to Argento for a major red herring near the film's end that could have spoiled the movie for me if it weren't a red herring. With Gabriele Lavia, Giuliana Calandra and Clara Calamai (Visconti's OSSESSIONE).