Obsession, released in the United States as The Hidden Room, is a 1949 British crime film directed by Edward Dmytryk. It is based on the 1947 novel A Man About a Dog by Alec Coppel, who also wrote the screenplay for the film. Obsession was entered into the 1949 Cannes Film Festival.

Edward Dmytryk was a Canadian-born American film director and editor. He was known for his 1940s noir films and received an Oscar nomination for Best Director for Crossfire (1947). In 1947, he was named as one of the Hollywood Ten, a group of blacklisted film industry professionals who refused to testify to the House Un-American Activities Committee (HUAC) in their investigations during the McCarthy-era Red Scare. They all served time in prison for contempt of Congress. In 1951, however, Dmytryk testified to the HUAC and named individuals, including Arnold Manoff, whose careers were then destroyed for many years, to rehabilitate his own career. First hired again by independent producer Stanley Kramer in 1952, Dmytryk is likely best known for directing The Caine Mutiny (1954), a critical and commercial success. The second-highest-grossing film of the year, it was nominated for Best Picture and several other awards at the 1955 Oscars. Dmytryk was nominated for a Directors Guild Award for Outstanding Directorial Achievement in Motion Pictures.