Factual error: When Marty goes to meet Mad Dog Tannen for the duel, in the background on the right side is the current flag of California. But that flag did not become the state flag of California until 1911, so would not have been around in 1885.
Back to the Future Part III (1990)
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Directed by: Robert Zemeckis
Starring: Christopher Lloyd, Michael J. Fox, Mary Steenburgen, Lea Thompson, Thomas F. Wilson, Elizabeth Shue
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More mistakes in Back to the Future Part III
Jennifer: Excuse me, Doc Brown. I brought this message back from the future and, well, now it's erased.
Doc: Of course it's erased.
Jennifer: But what does that mean?
Doc: It means your futures haven't been written yet. No one's has. Your future is what ever you make. So make it a good one, the both of you.
Trivia: Director Robert Zemeckis asked for Clint Eastwood's permission to use his name for BTTF 3. Clint Eastwood felt so honored that he said yes.
Answer: He simply has an absurdly low tolerance for alcohol, and whiskey is not a wise choice if this is the case. It helps set up the joke when Marty asks the bartender, "How many has he had?", and he replies by telling Marty, "Just the one", as we are meant to think Doc has been in the bar all night drinking away his sorrows.
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