Moffat discovered her love of performing early on, and in 1977 won a partial scholarship to train at the Lee Strasberg Institute in Los Angeles. She quickly embraced Strasberg's Method technique, and in 1984 moved to New York City to work and study at the Actor's Studio in Greenwich Village. Over the following years she built a steady supporting career in film and TV, with her debut performance in the true-crime network movie "Woman on Trial: The Lawrencia Bembenek Story" followed by a string of TV guest roles. After a brief appearance in "Two if by Sea," Moffat landed a memorable part as a flirtatious secretary in the historical comedy "Dick" (1999). Moffat next portrayed of a small-town art gallery guide in "Interstate 60: Episodes of the Road," and transitioned back to television with a recurring guest role on "Queer as Folk." The show, based on the popular UK series about a group of gay men and women, drew record ratings for the cable channel and broke new ground for its storytelling and depiction of the lives of its realistic, relatable gay characters. Moffat, who had moved back to Toronto in the late 1980s, was honored in 2008 with a Chalmers Award, which is gifted by a well-known Canadian family. After using the award to travel to Italy for an international conference of method writers and actors, Moffat was cast as Letitia Baldrige, Jackie Kennedy's (Katie Holmes) influential White House social secretary, in the multi-part "The Kennedys." She was next featured in the Canadian indie "Moon Point" as a quirky teen's mom, which she followed with a supporting arc on "Alphas" as the mother of an autistic teen with supernatural abilities. Rounding out the trifecta of maternal roles was "Mama," where she portrayed the great-aunt of a pair of long-abandoned sisters.