Widely considered the first gothic novel, and indeed an initiator of the whole genre, The Castle of Otranto is a 1764 novel by Horace Walpole. It tells the tale of the lord of a castle, Manfred, and his family. Manfred's son Conrad is about to be married to princess Isabella, but Conrad is killed; crushed to death by the fall of a huge helmet from above. In light of an ancient prophesy, this tragic event is especially ominous.
