The Boogeyman (1980)
The Boogeyman is a 1980 American supernatural slasher horror film directed by Ulli Lommel and stars Suzanna Love, John Carradine and Ron James. The film concerns two children, Michael and Lacey who are punished by their mother's boyfriend, but soon take revenge as Michael stabs the boyfriend with a kitchen knife while Lacey sees a hanged mirror witnessing the event. 20 years later, Lacey and Michael, now adults are being terrorized by an unseen force and now what they believe as, the spirit of their mother's boyfriend is starting to strike up for revenge on the two.
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