Over the course of her thirty-year career, Klein performed in radio comedies and soap operas, appeared in eight shows on Broadway, four films, and on thirteen television series.
[2] Broadway shows in which she appeared included Double Dummy (1936), Brooklyn, U.S.A. (1941), Uncle Harry (1942), Collector's Item (1952), The Immoralist (1954), Once Upon a Tailor (1955), Jane Eyre (1958), and Marathon '33 (1963).
[9] In the mid-1940s, Klein was active in the American Federation of Radio Artists (AFRA) and served as a delegate for New York at national conferences in 1943 and 1944.
[10] Klein was one of 56 delegates for New York at national conferences in 1943 and 1944, where she worked with others, including Donna Keath, Minerva Pious, Ann Shepherd, Selena Royle, and Hester Sondergaard.
[10][11] Along with Keath, Pious, Shepherd, Royle, Sondergaard, Klein was listed in the blacklisting publication, Red Channels: The Report of Communist Influence in Radio and Television in 1950.