An interest in amateur theater while in high school led her to Atlantic City in 1932, where she briefly worked as a chorus girl.

She received an Academy Award nomination and a Golden Globe for Best Supporting Actress for her performance as a lovelorn aunt in I Remember Mama (1948).

Over the next four decades, she worked in film and television, typically portraying maids, secretaries, waitresses, or gossips, often in Westerns, and had a recurring role as Henrietta Porter, a newspaper publisher, in Trackdown.

Corby appeared as the elderly Mrs. Lesh, the crooked car peddler, on CBS's The Andy Griffith Show.

She guest-starred, as well, on Wagon Train, Cheyenne, The Guns of Will Sonnett, Dragnet (several episodes), Rescue 8, The Restless Gun (two episodes), The Rifleman, The Life and Legend of Wyatt Earp, Fury, The Donna Reed Show, Frontier Circus, Hazel, I Love Lucy, Dennis the Menace, Tightrope, Bonanza, The Big Valley, Meet McGraw, The Virginian, Channing, Alfred Hitchcock Presents, Batman, Get Smart, Gomer Pyle, The Addams Family (as Lurch's Mother), The Beverly Hillbillies, The Invaders, Lassie, and Night Gallery.

From 1965 to 1967, she had a recurring role in the NBC television series Please Don't Eat the Daisies, based on an earlier Doris Day film.

She left the show November 10, 1976, owing to a massive stroke she had suffered at home,[3] which impaired her speech and severely limited her mobility and function.

In 1999, following several years of declining health, Corby died at age 87 at the Motion Picture & Television Country House and Hospital in Woodland Hills, Los Angeles.