Allyn Joslyn, the son of a Pennsylvania mining engineer, made his stage debut at 17. He was soon appearing regularly in Broadway productions, and headed for Hollywood in 1936, making his debut in They Won't Forget (1937). His nervous, at times dyspeptic demeanor and somewhat aristocratic looks fit in with the pompous, wealthy snobs he specialized in playing. Joslyn was also an extremely busy radio actor, performing on over 3,000 shows.