On the day of Conrad's wedding to princess Isabella, a horrible accident befalls the bridegroom. Fearing that this is the realization of a terrible ancient prophecy, Conrad's father Manfred believes that the fate foretold by the prophecy can only be averted if he marries Isabella himself. "The Castle of Otranto" - a 1764 novel by Horace Walpole - is credited with creating the genre of the gothic novel.