'The Man With The Golden Gun' (1965) by Ian Fleming

The Man with the Golden Gun is the twelfth and final novel in Ian Fleming's James Bond series and thirteenth Bond book overall. It was first published in the UK on 1 April 1965, eight months after the author's death. The novel was not as detailed or polished as the others in the series, leading to poor but polite reviews. Despite that, the book was a best-seller.
The story centres on the fictional British Secret Service operative James Bond, who had been posted missing, presumed dead, after his last mission in Japan. Bond returns to Britain via the Soviet Union, where he had been brainwashed to attempt to assassinate his superior, M. After being "cured" by the MI6 doctors, Bond is sent to the Caribbean to find and kill Francisco Scaramanga, the titular "Man with the Golden Gun".