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Run Fatboy Run is a 2007 comedy film written and directed by David Schwimmer, starring Simon Pegg, Thandie Newton, Dylan Moran, and Hank Azaria. The film follows Pegg's character, Gary King, as he attempts to run a 26.2-mile marathon in order to win back his former girlfriend, who left him after he cheated on her years earlier. Azaria plays Gary's friend and fellow runner, Sam.