On the big screen, she worked with Academy Award–winning actors Claire Trevor, Broderick Crawford, and Shirley MacLaine. On television, she appeared with such stars as Frank Sinatra, Bob Hope, Dean Martin, and Jerry Lewis. No Broadway musical written by theatrical royalty nor movie made by Oscar-winning talent in which Margaret had a part ever made the lasting impression with the public as her work with Groucho, Chico, Harpo, and Zeppo. She never got the laughs the brothers did, but without her the laughs would have been fewer in number. The boys were the clowns, the punch line tellers, and she was the straight lady who had the indispensable job of setting up the joke.