Castle Freak is a 1995 American horror film directed by Stuart Gordon, roughly based upon the short-story The Outsider by H. P. Lovecraft. It has elements of splatter/slasher films and references to Creature Features.
After inheriting a 12th century castle who belonged to a famed Duchess, John Reilly and his family travel to Italy to live there. Unbenownst to them, the duchess' son still lives in the dungeons of the castle. He breaks free, and tries to harm John and his family, killing others in the process. John must now save himself and his family from this castle's unknown inhabitant before the "castle freak" has his way with them.
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