Actress. As a child, she was trained for the opera and sang on the stage in both Europe and America. In 1910 she retired from the stage when she married millionaire industrialist John Moller Jr., but returned to the stage in 1918 after becoming a widow. Before long she had gained for herself a prominent name and reputation in musical comedy productions on vaudeville and in the theatre. Her track record on Broadway came to the attention of the Marx Brothers, who hired her to be in their Broadway production 'The Cocoanuts,' which began touring in 1925. In October of 1928 their next Broadway show, 'Animal Crackers,' opened, and Dumont was once again cast as the wealthy society dowager and their straight woman. In 1929 they filmed the screen version of 'The Cocoanuts,' which was one of the first true talking pictures. Dumont, who had only starred in three movies in uncredited roles prior, would go on to play in seven Marx Brothers movies. Besides 'The Cocoanuts,' she also appeared in 'Animal Crackers' (1930), 'Duck Soup' (1933), 'A Night at the Opera' (1935), 'A Day at the Races' (1937), 'At the Circus' (1939), and 'The Big Store' (1941). Her work in 'A Day at the Races' earned her a Best Supporting Actress Award from the Screen Actors Guild. According to legend, she never understood the jokes the Marx Brothers, and in particular Groucho, were making at her expense, although a number of people who knew her disagreed, saying that she knew all the time what was really going on and understood these jokes perfectly well. Although she is best-remembered for her work with the Marx Brothers, she also made movies with a number of other comedians of the day, such as Laurel and Hardy, W.C. Fields, Abbott and Costello, Danny Kaye, Jack Benny, and Red Skelton. These other movies include 'The Dancing Masters' (1943), 'Never Give a Sucker an Even Break' (1941), 'Little Giant' (1946), 'Bathing Beauty' (1944), 'Anything Goes' (1936), 'High Flyers' (1937), and 'About Face' (1942). After 1946 she only appeared in a few more movies, and also occasionally appeared on television shows. Dumont's final acting role was on the television show 'The Hollywood Palace,' just days before her death. It was only fitting that this appearance reunited her with Groucho Marx, who had earlier tried in vain to get her to appear on his show 'You Bet Your Life.' He was hosting this episode of 'The Hollywood Palace,' in which they reenacted a scene from 'Animal Crackers.' Shortly after this episode was taped, she died of a heart attack.