 Shortly after her college graduation, Bosworth became a member of the Actors Studio in Manhattan, where she studied under master teacher Lee Strasberg.Arthur Penn cast her as the lead in her first professional play, a pre-Broadway tryout of James Leo Herlihy’s "Blue Denim", about the consequences of teenage pregnancy and abortion.Bosworth appeared in several Broadway shows during the 1950s and 1960s, including "Inherit the Wind", "Small War on Murray Hill" (directed by Garson Kanin), and Jean Kerr's "Mary, Mary" (where she understudied from 1961-1965 before being cast as the lead for the end of the play's run).