The White Priory Murders is a mystery novel by the American writer John Dickson Carr (1906-1977), who published it under the name of Carter Dickson. It is a locked room mystery and features his series detective, Sir Henry Merrivale, assisted by Scotland Yard Inspector Humphrey Masters. Marcia Tait is a Hollywood star who has come to England to make a historical film. She is found beaten to death in the Queen's Mirror pavilion, the 17th-century trysting place of King Charles II and Lady Castlemain. The problem is particularly puzzling because the pavilion is surrounded by newfallen snow, with only one set of footprints leading to it and none leading away. The suspects include a man who thought he was marrying her - and her husband, whose marriage was unknown to all. Sir Henry Merrivale lends a hand to Inspector Masters in the investigation, but is too late to stop the second murder before Merrivale solves the case.