The Red House Mystery is a "locked room" whodunnit by A. A. Milne, published in 1922. It was Milne's only mystery novel.
The setting is an English country house, where Mark Ablett has been entertaining a house party consisting of a widow and her marriageable daughter, a retired major, a wilful actress, and Bill Beverley, a young man about town. Mark's long-lost brother Robert, the black sheep of the family, arrives from Australia and shortly thereafter is found dead, shot through the head. Mark Ablett has disappeared, so Tony Gillingham, a stranger who has just arrived to call on his friend Bill, decides to investigate. Gillingham plays Sherlock Holmes to his younger counterpart's Doctor Watson; they progress almost playfully through the novel while the clues mount up and the theories abound
Alan Alexander Milne (/mɪln/; 18 January 1882 – 31 January 1956) was an English author, best known for his books about the teddy bear Winnie-the-Pooh and for various poems. Milne was a noted writer, primarily as a playwright, before the huge success of Pooh overshadowed all his previous work. Milne served in both World Wars, joining the British Army in World War I, and as a captain of the British Home Guard in World War II.[1]
He was the father of bookseller Christopher Robin Milne, upon whom the character Christopher Robin is based.