Arnold Schwarzenegger is a famous Austrian-American actor and the former governor of California. He appeared in the episode "It's a Jersey Thing", where he refused Randy Marsh's plea for help against the Jersey invasion. He is mentioned again in "T.M.I." where Butters and the boys discuss his love child scandal which only made the headlines a day before the episode aired.
Arnold wears a black suit, a white undershirt, and a purple tie. He also has a very noticeable gap in his two front teeth.