The Castle of Otranto tells the story of Manfred, lord of the castle, and his family. The book begins on the wedding-day of his sickly son Conrad and princess Isabella. Shortly before the wedding, however, Conrad is crushed to death by a gigantic helmet that falls on him from above. This inexplicable event is particularly ominous in light of an ancient prophecy, "that the castle and lordship of Otranto should pass from the present family, whenever...