In 1987, Wagner wrote a series of books with Robert M.Klein about using acupressure to achieve results akin to a surgical facelift.Her primetime network television debut was in the series Adam-12 ("Million Dollar Buff"), and she went on to appear in a dozen other Universal shows, including Owen Marshall: Counselor at Law, The F. I., Sarge, and Night Gallery (1971, as the nurse in the episode: "The Diary"). In 1973, Wagner branched into film roles when Universal cast her in Two People, which was her first feature film and her first lead role.Between 19, she appeared in five episodes of Universal's Marcus Welby, M. She also co-starred in the 20th Century Fox film The Paper Chase the same year, playing the daughter of the stern law professor Kingsfield.In 1994, she wrote one of the first "celebrity" vegetarian (and mainly vegan) cookbooks, High Road to Health.
When she was seven years old, Wagner's parents divorced and her mother moved with her to the northeast Los Angeles neighborhood of Eagle Rock, near Pasadena.
Another relocation with her mother and stepfather, Ted Ball, brought Wagner to Portland, Oregon, where she attended David Douglas High School and appeared in a number of school plays.
Wagner attended the University of Oregon for part of her freshman year before she transferred to Mount Hood Community College for a short period of time.
Also in the 1980s, Wagner co-starred as Sylvester Stallone's ex-wife in his 1981 movie Nighthawks and starred in two more weekly television series, Jessie and A Peaceable Kingdom (1989), though both of these were short-lived.
In 1983, she also appeared in an episode of Lee Majors' series The Fall Guy.