Aguirre, The Wrath of God. I studied it at uni and wrote an essay where I explained that the main character couldn't be a symbol of both fascism AND a film director, because that would mean the director was calling himself a fascist. My lecturer's response was something like "why not?". I was a very black-and-white thinker at that time, and his response was eye-opening for me.
It's fascinating how he was begging some investor about how he had to make the movie Fitzcarraldo, because if he didn't, his life would be purposeless (I do hope I'm remembering this right). It got me wondering how he got away with things like forcing his crew to carry tonnes of ship over a mountain, but, also why shouldn't he get away with it, why should there be a strict construct of what's allowed or not.