Trivia: The make-up process to transform Klaus Kinski into Count Dracula took four hours every day of the shoot.
Trivia: The person who sticks his foot into the coffin and gets his toe bitten by a rat is the film's director, Werner Herzog.
Trivia: All rats used in this movie where imported from Hungary and were originally white. Only black rats can pass the plague, so all rats where painted black or grey right before the film shots. (01:33:35)
Answer: True, though the rats comment was deliberate hyperbole. Kinski suffered from mental illness much of his life. He was often volatile, erratic, disruptive, and sometimes violent on movie sets. Kinski and Herzog had a long professional collaboration but also a friendship pre-dating Herzog's directing career. Otherwise, though Herzog admired Kinski's talent, he probably would never have tolerated working with him; he is the only director who worked with him more than once. Herzog did a documentary about Kinski after his death, which included footage of his on-set rants. Clips are on YouTube.
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Moreover, Herzog was initially reluctant to hire Kinski in Fitzcarraldo movie because he was afraid that Kinski would go "totally bonkers" if trapped in the Amazon for any length of time, and his fears proved to be well-founded.
To correct a slight factual error in the answer: Director Alfred Vohrer worked on more movies with Kinski than Herzog did.
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