Adrian Malcolm Conan Doyle (19 November 1910 – 3 June 1970) was the youngest son of Sir Arthur Conan Doyle and his second wife Jean, Lady Doyle or Lady Conan Doyle. He had two siblings, sister Jean Conan Doyle and brother Denis, as well as two half-siblings, sister Mary and brother Kingsley.
Adrian has been depicted as a racing car driver, big-game hunter, explorer, and writer. Biographer Andrew Lycett calls him a "spendthrift playboy" who (with his brother Denis) "used the Conan Doyle estate as a milch-cow".
He married Danish-born Anna Andersen, and was his father's literary executor after his mother died in 1940. He founded the Sir Arthur Conan Doyle Foundation in Switzerland in 1965. On his death, Jean took over as their father's literary executor. […]
Adrian Conan Doyle produced additional Sherlock Holmes stories, some with the assistance of John Dickson Carr. The basis of his production was to complete those tales referenced in his father's stories, which his father had never written. (Carr had published an "authorized" biography of Sir Arthur in 1949.) These additional Sherlock Holmes tales were written in 1952 and 1953, and a hardcover collection of the stories was published as The Exploits of Sherlock Holmes in 1954. They have been reissued subsequently, while other authors have also written Sherlock Holmes stories based on the same references within the original tales.