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Although the film itself is completely fictional, the Coen brothers claim that many of the events that take place in the movie were actually based on true events from other cases that they threw together to make one story. Joel Coen noted:
"We weren't interested in that kind of fidelity. The basic events are the same as in the real case, but the characterizations are fully imagined...If an audience believes that something's based on a real event, it gives you permission to do things they might otherwise not accept."