In this ghostly detective story, Lord Montbarry is engaged to marry his cousin, Agnes Lockwood, when he meets and falls in love with the beautiful Countess Narona. Against the advice of his family, Montbarry breaks his engagement to Agnes and proposes to the countess. After checking that Montbarry's life is heavily insured, the countess agrees to marry him, but insists her 'brother', Baron Rivar, must come and live with them in their crumbling palace in Venice. Dark events follow involving murders, mysteries and missing people. Eventually the palace is turned into a hotel, but then strange things begin to happen.