A blind man who likes puzzles happens to overhear a enigmatic conversation about a murder and calls in the help of an American reporter. The journalist witnesses a murder attempt in an art gallery. The murder is masked by four more murders.This feature début by Dario Argento, who used to be a film critic and scriptwriter for Sergio Leone, was a major success at the box office. Argento expanded on the archetypes of Italian horror of Riccardo Freda and Mario Bava, but also added all kinds of things: a crazy plot, a hard final scene and various techniques to disorientate and lead the viewer into a nightmare that lasts as long as the film. Many imitators followed, but Argento remains the best. Some scenes are inspired by Fritz Lang, others by Alfred Hitchcock. A doctor from Turin with the same name as a character in the film, insisted that it was changed. (SdC)