The daughter of action star Jack Holt, Elizabeth Marshall Holt reportedly picked the name Jennifer after reading Don Byrne's novel Destiny Bay. Holt studied with famed Russian actress Maria Ouspenskaya and understudied Teresa Wright in Life With Father (1939) on Broadway, but a leading role in Two for the Show (1940) went instead to Betty Hutton. Her brother Tim Holt secured her the femme lead in a Hopalong Cassidy Western, Stick to Your Guns (1941); much to her chagrin, however, producer Harry Sherman insisted on billing her as Jacqueline Holt in honor of her famous father.
She was allowed to use the Jennifer Holt moniker while under contract to Universal (1942-1943), and as such, starred in the 1943 serial Adventures of the Flying Cadets and a host of B-Westerns featuring the likes of Johnny Mack Brown, Tex Ritter, and Russell Hayden. But although the films were above average for low-budget action fare, she was only drawing a weekly salary of 75 dollars and bolted when she discovered that she could make much more as a freelance actress.
Returning to Universal at regular intervals -- but now demanding 350 dollars a picture -- Holt became a regular B-Western leading lady at bottom-of-the-barrel producer PRC where, in 1948's The Hawk of Powder River, she even got to play a nasty female outlaw. The Eddie Dean oater remained her favorite film, but the B-Western genre was in decline and she left Hollywood to star in industrial films in Chicago. She also entered the field of early children's television, earning a 1949 TV Guide award for The Adventures of Uncle Mistletoe and Aunt Judy, a local morning show, and a 1951 Peabody Award for the ABC series Panhandle Pete and Jennifer.
Married no less than seven times -- her second husband, William Bakewell, had been her co-star in the 1945 serial Hop Harrigan -- and retiring from performing in 1958 after a guest role on television's Perry Mason, Jennifer Holt later settled in Cuernavaca, Mexico, and the United Kingdom. She returned to the United States often, however, becoming a welcome guest speaker at various B-Western and serial fairs.