"The Hundred Days of the Dragon" is an episode of the original The Outer Limits television show. It first aired on 23 September 1963, during the first season.

An Asian government develops a reliable means of changing a person's physical appearance, and uses it to replace a U.S. presidential candidate with a spy.

An unspecified Asian government plans to take over America by infiltrating and substituting all the officials at the White House. During the presidential campaign, William Lyons Selby (the candidate predicted to win the next election) is murdered and then replaced by a lookalike spy. Selby is elected, and the impostor assumes the office of the President of the United States. Though he fools the nation at large during his first few months in office, his daughter, Carol, soon begins to suspect that the man in the White House is not her father. She voices her concerns to the Vice President, Ted Pearson, who disbelieves her, at first, until he is targeted for substitution by an assassin who breaks into his home during their conversation, is discovered lying in wait, and is chased off before he can commit the act already in the guise of Pearson. Now convinced that Carol's story is valid, Pearson informs the head of the Secret Service detail assigned to the President of the plot, and the suspicion that Selby is an impostor. After several failed attempts by the Secret Service in identifying Selby through dental records and other means, the leader of the Asian government confers with his spy at the White House prior to a planned summit meeting, where he reveals the second phase of their operation to substitute various cabinet members, heads of state, and private industry tycoons. When Selby arranges a second attempt at replacing his Vice President, the perpetrators are captured, brought before the President during a state reception and exposed, along with Selby, himself, with the real Pearson arresting and then charging him with murder and attempting to overthrow the United States government.

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