Peter O'Toole is Peter Plunkett, the owner of a dilapidated Irish castle which has been converted to a bed and breakfast supplying the only employment for the local villagers. Owing money to an Irish-American businessman by the name of Brogan, Plunkett has the idea to turn the castle into "the most haunted castle in Europe" for the tourist trade, inspired by his mother's stories of the castle's history of ghosts. He and his wacky staff of Irish characters set about creating ghost costumes and effects for their first group of American lodgers.