After Miss Jane Marple is made a trustee of a merchant marine training vessel, a fellow trustee is poisoned, and ship's officers are later murdered after she comes on board.
Margaret Rutherford - Miss Marple Lionel Jeffries - Captain Rhumstone Charles Tingwell - Chief Inspector Craddock William Mervyn - Commander Breeze-Connington Joan Benham - Matron Alice Fanbraid Stringer Davis - Mr Stringer Nicholas Parsons - Dr. Crump Miles Malleson - Bishop Faulkner Henry Oscar - Lord Rudkin Derek Nimmo - Sub-Lieutenant Humbert Gerald Cross - Lieutenant Commander Dimchurch Norma Foster - Assistant Matron Shirley Boston Terence Edmond - Sergeant Bacon Francis Matthews - Lieutenant Compton Lucy Griffiths - Millie Bernard Adams - Dusty Miller Tony Quinn - Kelly Edna Petrie - Miss Pringle Roy Holder - Petty Officer Lamb Ivor Salter - Police Sergeant Henry Longhurst - Cecil Ffolly-Hardwicke Desmond Roberts - Sir Geoffrey Bucknose Billy Dean - Police Constable Colin McKenzie - Officer Arnold Schulkes - Officer Paddy Smith - Steward