Everybody knows Hamill because he played Luke Skywalker in the original Star Wars trilogy. This instantly made him a superstar even if he lacked the on-screen charisma of Harrison Ford. But the young Jedi knight had plenty of admirers in Hollywood. Surprisingly, Hamill disappeared out of nowhere and never made it as a leading man.
Directors typecast him and this felt frustrating so he preferred to pursue voice acting. It says a lot that his second-most famous role was The Joker in the animated Batman series. However, Hamill agreed to return and play an older version of Skywalker in the new Star Wars trilogy (via Screenrant).