O'Keeffe got his first big break playing the title role in the 1981 version of Tarzan, the Ape Man.
Subsequently, he transferred to University of the South in Sewanee, Tennessee and became a small college All-American playing both tight end and linebacker.
After studying political science and psychology, O'Keeffe became a prison counselor in the Tennessee penal system for a year or two where he became manager of playground activities and inmate weightlifting programs.
Although O'Keeffe is known for his big break as Tarzan, he is also remembered for his performances in the title role of the first three Ator sword and sorcery films produced in Europe in the 1980s.
The episode, which soon became immensely popular among fans, included one of the most-quoted quips in the show's history: "How much Keeffe is in this movie anyway?"