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Keitel portrayed the nefarious character "Sport" in the 1976 cinematic masterpiece "Taxi Driver." Sport's occupation as a pimp epitomized the gritty underbelly of New York City, where the protagonist Travis Bickle navigated a world overrun by crime, prostitution, and moral ambiguity. Keitel's menacing presence solidified his role as a symbol of the city's corruption, leaving a lasting impact on the audience.