Marguerite McNamara was an American stage, film, and television actress and model from the United States. McNamara began her career as a teenage fashion model. She first came to public attention as Patty O'Neill in the 1951 national tour of F. Hugh Herbert's The Moon Is Blue which ran concurrently with the original Broadway production. In 1952 she succeeded Barbara Bel Geddes in that role in the Broadway production. Both productions were directed by Otto Preminger, and Preminger also directed McNamara in that role in the controversial 1953 film adaptation of that work. She earned an Academy Award nomination for Best Actress for her role in the film.

The Moon Is Blue is a 1953 American romantic comedy film produced and directed by Otto Preminger and starring William Holden, David Niven, and Maggie McNamara. Written by F. Hugh Herbert and based on his 1951 play of the same title, the film is about a young woman who meets an architect on the observation deck of the Empire State Building and quickly turns his life upside down. Herbert's play had also been a huge success in Germany, and Preminger decided to simultaneously film in English and German, using the same sets but different casts. The German-language film version is Die Jungfrau auf dem Dach.