Selmon started her acting career in the late 1970s with her part as Sheila Moran in the Bill Cosby/Sidney Poitier crime comedy A Piece of the Action (1977) which also features Trek performers Marc Lawrence, Henry Kingi, Sr., Bob Minor, and Julius LeFlore. The following years she had guest roles in the drama series Roots (1977, starring LeVar Burton), The White Shadow (1979 and 1980, with Joan Pringle and TNG co-star Jonathan Frakes), and Hill Street Blues (1981, with James Sikking, Mark Metcalf, Tony Plana, and Barbara Bosson) and a featured role as Harbinger's sister in the 1982 comedy Wacko (with Charles Napier).