Osa Massen (born Aase Madsen Iversen) was a Danish actress who became a successful movie actress in Hollywood. She became a naturalized citizen of the United States in 1941.
Massen's first film was Kidnapped (1935). She notably appeared as Melvyn Douglas' unfaithful wife dealing with blackmailer Joan Crawford in A Woman's Face (1941). She also appeared as a mysterious woman with something to hide in Deadline at Dawn (1946). She also starred with Lloyd Bridges in the movie Rocketship X-M (1950), the first space adventure of the post-World War II era.
