Scott began appearing on the small screen in the early 50s in such anthology series as "The Web" and "Teller of Tales". She hosted and narrated "Modern Romances" (NBC, 1954-58). For much of the 60s, she concentrated on stage work, making occasional guest appearances on shows ranging from "The F.B.I." to "Columbo". When she became more active in the 70s, it was often in character roles. Scott had the recurring role of Bob's mother on "The Bob Newhart Show" and also appeared as the mother of Sue Ellen Ewing (Linda Gray) on "Dallas" in 1979 and 1985. In the short-lived primetime soap "Secrets of Midland Heights" (1980-81), she was the matriarch of a wealthy but morally bankrupt family. In a fascinating episode of "Murder, She Wrote" in 1987, Scott, Jeffrey Lynn and Harry Morgan reprised their screen roles in 1949's "Strange Bargain". The plot presumed to find the real killer and incorporated scenes from the original film.
In addition to acting, Scott had a secondary career as a producer with both the (1978) Broadway and (1991) film versions of "First Monday in October", a comedy drama about the first woman appointed to the Supreme Court. The former paired Henry Fonda and Jane Alexander, the latter Walter Matthau and Jill Clayburgh.