Along with The Thirty-nine Steps, this is the most admired film from Alfred Hitchcock's early directorial career. The comedy-suspense-thriller centers around a group of British types on a train trip from England to central Europe. A young woman (Margaret Lockwood) seeks the aid of a fellow passenger (Michael Redgrave) in an attempt to locate a charming old lady (May Whitty) she had met earlier on the train and who now is apparently missing.