She attended Harding Junior High School and Classen High School there, then took a job at a U.S. Army induction center as a stenographer. She left to study acting at Oklahoma City University, starring in a production of "Romeo and Juliet". She saved money and made a two-week trip to Hollywood in hopes of landing a movie career. An agent working for Samuel Goldwyn came across her at a drug store and brought her in for a screen test. Goldwyn offered her a contract, assigning her to a speech tutor to minimize her southern accent and to local theaters to gain experience. She was part of a Pasadena Playhouse production of "Little Women" and was part of the cast of "Life With Father" in Boston, Massachusetts in 1944. At the suggestion of Goldwyn's wife, she changed her name to Cathy O'Donnell.
O'Donnell made her film début as an uncredited extra in the 1945 film Wonder Man. A year later she was picked to star opposite Harold Russell in The Best Years of Our Lives, directed by William Wyler. In April 1948 she married Wyler's brother, Robert.
O'Donnell was lent to RKO Pictures for the film noir They Live by Night in 1948. She reunited with Farley Granger in the 1950 film, Side Street. Her husband co-wrote the script for the 1951 film "Detective Story", directed by William Wyler, in which she played the role of Susan Carmichael. She played Jimmy Stewart's love interest in the 1955 western "The Man from Laramie" and concluded her film career with the role of Tirzah, Judah Ben-Hur's sister, in the 1959 William Wyman epic "Ben-Hur".
During the 1960s, O'Donnell appeared on several television series, including "Perry Mason", "The Rebel", "Man Without a Gun" and "Bonanza". She died of a cerebral hemorrhage related to cancer in April 1970. She is buried at Forest Lawn Memorial Park in Glendale, California.
- "Cathy O'Donnell" (July 5, 2021) Wikipedia - accessed July 6, 2021