Four Flies on Grey Velvet

Four Flies on Grey Velvet Italianmosche di velluto grigio is a 1971 Italian giallo film written and directed by Dario Argento. The film is the third in director Argentos Animal Trilogy, which started with The Bird with the Crystal Plumage and The Cat o Nine Tails.

Roberto returns home and lies in bed awake as his wife Nina Mimsy Farmer lies beside him. The next day, Roberto reads the newspaper describing the dead man and he receives a letter containing the identification of a certain Carlo Marosi, the man who Roberto stabbed. That evening at a gettogether of several band members and friends at his house, one of the guests talks about beheading executions in Saudi Arabia, and Roberto looks through some record albums and sees the photos of the incident. Amelia Maria Fabbri, the maid, sees him and the photos, but does not tell him that she knows. That night, Roberto has a disturbing dream about him being beheaded in a coliseum in Saudi Arabia when he wakes up after hearing a noise. Roberto looks around and a cord is wrapped around his neck. The masked person tells Roberto, he could kill him now, but will not for he is not finished with him, and knocks him out before running away. Nina walks in and asks her husband what is wrong and he finally admits to the accidental stabbing and subsequent harassment, and says that they cannot go to the police.Roberto goes to see Godfrey Bud Spencer whom Robertos annoys by nicknaming him God. Godfrey is a beatnick artist living in a shack outside Rome with his colleague, a conartist known only as the Professor Oreste Lionello. Roberto confides in them about his problem and Godfrey suggests having the Professor keep an eye on him. ........

Source: Wikipedia