An Angel for Satan (original title Un Angelo per Satana) is a 1966 Italian horror movie about a young woman (Barbara Steele) who begins acting strangely after an old statue is recovered from a nearby lake. The film costarred Anthony Steffin and Claudio Gora.
When an old statue is pulled out of a lake, Count Montebruno (Gora) hires young sculptor Roberto (Steffan) to restore it. Roberto does some research and finds that the damaged statue was original modeled after the beautiful Maddalena (Steele) and destroyed by her jealous sister Belinda. Fortunately, Count Montebruno's niece Harriet (Steele) looks exactly like Maddalena, and Roberto uses her to restore the statue.
Unfortunately, the statue's restoration causes Harriet to start acting strangely, taunting and seducing just about everyone in her life and driving people to murder and suicide. The townsfolk suspect that Harriet has been possessed by Belinda. However, Roberto discovers that Count Montebruno has been hypnotizing Harriet into carrying out his orders, creating havoc so that the townspeople will lynch Harriet (and causing her substantial inheritance to pass to the Count). Roberto catches the Count red-handed and solves the mystery- or has he?