This Italian and Spanish thriller movie debuted in 1970. The movie follows Minou, a housewife married to an affluent businessman named Peter. A stranger attacks the naive housewife in the middle of the night and claims her husband is a murderer. She is later shown additional evidence that will indict her husband for the killing. The mystery man uses this to blackmail Minou into sleeping with him, which he records. When Minou's best friend Dominique seems to be involved with the blackmailer, things start to spin out of control. Who is he, is her friend involved and is Peter really a cold blooded killer or has she been tricked all along?