Paul Dehn (5 November 1912 – 30 September 1976) was an Oscar-winning British screenwriter, best known for Goldfinger, The Spy Who Came in from the Cold, Planet of the Apes sequels and Murder on the Orient Express. Dehn and his partner, James Bernard, won the Academy Award for best Motion Picture story for Seven Days to Noon. Paul Dehn was born in 1912 in Manchester, England. He was educated at Shrewsbury School, and attended Brasenose College, Oxford. While at Oxford, he contributed film reviews to weekly undergraduate papers. He began his career in 1936 as a film reviewer for several London newspapers. During World War II he was stationed at Camp X in Canada. This was one of several training facilities operated by Special Operations Executive to train spies and special forces teams. He was the Political Warfare officer from 1942–44 and held the rank of Major. Dehn took part in missions in France and Norway. He narrated the 1951 film Waters of Time and later wrote plays, operettas, and musicals for the stage. He wrote the lyrics for songs in two films, The Innocents (1961) and Moulin Rouge (1952).

In 1949 or 1950, Dehn began a professional collaboration with composer James Bernard. Dehn asked Bernard to collaborate with him on the original screen story for the Boulting Brothers film Seven Days to Noon (1950). Through the 1960s, Dehn concentrated on screenwriting for espionage films, notably Goldfinger (1964), The Spy Who Came in from the Cold (1965), and The Deadly Affair (1967). He later wrote the screenplays for the four Planet of the Apes sequels and the libretto for William Walton’s opera The Bear; he also wrote libretti for two operas by Lennox Berkeley, A Dinner Engagement and Castaway. His last screenplay was for Sidney Lumet’s all-star Murder on the Orient Express (1974), based on the Agatha Christie whodunit, for which he was nominated for an Academy Award for Best Adapted Screenplay. Paul Dehn (pronounced “Dane,” as in “the melancholy”) resurrected or reinvented at least three genres given up for dead at the time: the British mystery, the Shakespeare adaptation, and the spy film.