Gangs of New York - How Old Is Bill the Butcher?
In the first part of the movie, when Bill the Butcher is on the docks, arguing with Boss Tweed about how immigrants should not be allowed into America, he says that his father gave his life fighting for America in 1814. Later, Bill tells Amsterdam that he is 47 years old. This part of the movie is in 1863. This cannot be, because Bill's father would have died two years before he was born.