Wanting a career in films, Mara Corday came to Hollywood while still in her teens and found work as a showgirl at the Earl Carroll Theatre on Sunset Boulevard. Her physical beauty brought jobs as a photographer's model that led to a bit part as a showgirl in the 1951 film Two Tickets to Broadway. She signed on as a Universal International Pictures (UI) contract player where she met actor Clint Eastwood with whom she would remain lifelong friends. With UI, Corday was given small roles in various B-movies and television series. In 1954 on the set of Playgirl she met actor Richard Long. Following the death of Long's wife, the two began dating and married in 1957.
Her roles were small until 1955 when she was cast opposite John Agar in Tarantula, a Sci-Fi B-movie that proved a modest success. She had another successful co-starring role in that genre (The Black Scorpion) as well as in a number of Western films. Respected film critic Leonard Maltin said that Mara Corday had "more acting ability than she was permitted to exhibit."