A disturbing package leads Detective Cormoran Strike and his assistant Robin Ellacott to investigate four dangerous murder suspects in this "magnetic" British mystery (Michiko Kakutani, New York Times) that inspired the acclaimed HBO Max series C.B. Strike.    When Robin Ellacott opens an unexpected delivery, she is horrified to discover that it contains a woman's severed leg. Her boss, private detective Cormoran Strike, is less surprised but just as alarmed. He suspects that