Thelma Ritter was an American supporting and character actress from the 1940s until her death in 1969.
Ritter was born in Brooklyn, New York in 1902. After appearing in high school plays and stock companies

Summer stock theatre

Summer stock theatre is any theatre that presents stage productions only in the summer within the United States. The name combines both the seasonal time of year with the tradition of staging shows by a resident company, reusing stock scenery and costumes...

, she trained as an actress at the American Academy of Dramatic Arts

American Academy of Dramatic Arts

The American Academy of Dramatic Arts is a fully accredited two-year conservatory with facilities located in Manhattan, New York City – at 120 Madison Avenue, in a landmark building designed by noted architect Stanford White as the original Colony Club – and in Hollywood, California...

. She established a stage career but took a hiatus to raise her two children by her husband, Joseph Moran, an actor turned advertising executive.
Ritter did stock theater and radio shows early in her career, without much impact.