On the day of his wedding, Conrad, heir to the house of Otranto, is killed under mysterious circumstances. His calculating father, Manfred, fears that his dynasty will now come to an end and determines to marry his son's bride himself--despite the fact he is already married. But a series of terrifying supernatural omens soon threaten this unlawful union, as the curse placed on Manfred's ancestor, who usurped the lawful Prince of Otranto, begins to...