“[Hal] Miller received his Actors’ Equity Association card in 1966 while working with Joseph Papp in Henry V and his Screen Actors Guild card in 1971 after being hired by Columbia Pictures. He appeared in the Lizzie Borden film Born in Flames … In 1968 he was invited to perform experimental, integrated theater for one season at Arena Stage in Washington, D.C. From 1972 until 1974, Miller played Gordon on Sesame Street. Miller made the decision to leave Sesame Street for mainstream acting. [In his later career, he went on to performing and singing in Europe and Asia.]”

–Wikipedia.org