Can you name the actors who started in their mid-to-late 20s?#1Posted: 5/4/13 at 4:32pm. It seems like all of the famous theater actors started acting when they were teenagers or younger. believe she was already 40 when she booked Best in Show.). In terms of the much rarer actually-had-another-career-and-started-late, Ken Jeong comes to mind. He practiced Internal Medicine before winning a Stand-Up contest when he was 28, and booked his first film role ten years later.