A man is murdered by a female hitch-hiker who cuts out his heart with a sharp hook. While noting its similarity to another recent killing, Police Inspector Clifford hears on the radio about a book by local writer Natalie, concerning a 17th Century countess who kept an eagle that tore out her husband's heart after he locked her up, in addition to her many subsequent lovers. Clifford contacts Natalie to find out more and his suspicion soon falls on Mrs Henska, an elderly European who is descended from the count...