After her time as a chorus girl on Broadway, Dowling followed her elder sister Constance to Hollywood. Her first credited film role was that of Gloria, barfly and drinking companion to fellow alcoholic Ray Milland in the 1945 film The Lost Weekend. She next appeared in The Blue Dahlia, which starred Alan Ladd and Veronica Lake.

In Italy, Dowling starred in several acclaimed films including Bitter Rice. She appeared in Orson Welles's European production of Othello in 1952, playing Bianca.

Dowling dated Billy Wilder during the 1940s and married three times. In 1952, she became band leader Artie Shaw's seventh wife. They had a son, Jonathan, before divorcing in 1956. Later that same year, on April 27, 1956, Dowling married film executive Robert F. Blumofe; they divorced in 1959. She married Leonard Kaufman on April 20, 1960, to whom she remained married until her death in 2004.

Dowling shared the "Best Ensemble Performance" Outer Critics Circle Award for 1972-1973 for her performance in a revival of The Women on Broadway. Her other Broadway credits include Panama Hattie (1942), Banjo eyes (1942), Beat the Band (1942), and New Faces of 1943 (1943).

Dowling died at Cedars-Sinai Medical Center in Los Angeles, California on June 18, 2004 at age 81. She is buried at Holy Cross Cemetery, Culver City, California.

Upon returning to the United States, much of Dowling's work was in theater and on television. She appeared in such television shows as Have Gun – Will Travel, Cheyenne, Alfred Hitchcock Presents, Science Fiction Theater, Bonanza, Perry Mason, The Andy Griffith Show and, late in her career, The Incredible Hulk, Kojak, and finally, The Dukes of Hazzard in 1984. She co-starred with Bob Cummings and Julie Newmar in the sitcom My Living Doll.