Beatty started his career making appearances on television shows such as "Studio One" (1957), "Kraft Television Theatre" (1957), and "Playhouse 90" (1959). He was a semi-regular on "The Many Loves of Dobie Gillis" during its first season (1959–60). Beatty made his movie debut in Elia Kazan's "Splendor in the Grass" (1961), opposite Natalie Wood.