Actor Josh Brolin broke his shoulder in a motorcycle accident only two days after winning the part of Llewellyn Moss in No Country. He was worried about losing the part, but in the end it all worked out: Brolin's character gets shot in the shoulder early in the movie anyway, so the busted shoulder just made the whole thing more realistic.
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No Country for Old Men's biggest contender for the Best Film Oscar in 2007 was Paul Thomas Anderson's There Will Be Blood. Turns out that this movie was shot really close to where the Coens shot No Country, and one day the Coens even had to stop filming because of a giant cloud of smoke that had wafted over from Anderson's set.
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Anton Chigurh uses a semi-automatic shotgun throughout this movie, but we never do we see an empty shell casing come out of his gun. That's factually impossible, just so you know.
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