An American film, stage, and television actress of Irish-Norwegian origins, born as Margaret Ann Knudsen in Duluth, Minnesota, USA. She received a star on the Hollywood Walk of Fame in 1960 for her television works. She married three husbands and had four children. Her most important works include The Big Sleep (1946), Humoresque (1946), and Istanbul (1957). Her father who worked as the head of Duluth Fire Department. She studied violin as a child and practiced acting in school plays. Her family moved to Chicago, where she began her career in radio drama, and at the age of 17, she made her way to Broadway. In 1945, she went to Hollywood to appear in films and signed a contract with Warner Bros. to present the movie A Stolen Life (1946). She provided an important role in the movie The Big Sleep (1946), for which she received praise from critics. Then she presented the movie Never Say Goodbye (1946) with Errol Flynn, and Humoresque (1946) with John Garfield, but Warner Bros. loaned her to 20th Century Fox and Monogram to star in B-movies, such as Rosses Are Red (1947). She was a television star and guest-starred in prime-time series, such as So This Is Hollywood (1955) in 24 episodes. Her arthritis led to her early retirement from acting in 1965, and she spent most of her remaining few years under the care of her good friend, actress Jennifer Jones, who paid for her treatment until she died in Encino, California, USA on July 11, 1980, of cancer.