In the early 1960s, McNair made several musical shorts for Scopitone, a franchise of coin-operated machines that showed what were the forerunners of today's music videos. In 1967 McNair traveled with Bob Hope to Southeast Asia to perform for U.S. troops during the Vietnam War. McNair's acting career began on television, as a guest on series such as "Dr. Kildare", "The Eleventh Hour", "I Spy", "", "Hogan's Heroes" and "McMillan and Wife". McNair posed nude for "Playboy" in the October 1968 issue. She caught the attention of the movie-going public with her much-publicized nude sequences in the gritty crime drama "If He Hollers, Let Him Go!" (1968) opposite Raymond St. Jacques, then donned a nun's habit alongside Mary Tyler Moore for "Change of Habit" (1969), Elvis Presley's last feature film. She portrayed Sidney Poitier's wife in "They Call Me Mister Tibbs!" (1970) and its sequel, "The Organization" (1971), and George Jefferson's deranged ex-girlfriend Yvonne in "The Jeffersons" (1984).