Werner Herzog - On the filming of Aguirre, the Wrath Of God. Read it.

The low budget precluded the use of stunt men or elaborate special effects. The cast and crew climbed up mountains, hacked through thick jungle, and rode ferocious Amazonian river rapids on rafts built by natives. At one point, a storm caused a river to flood, burying the film sets underneath several feet of water and destroying all of the rafts built for the film. This flooding was immediately incorporated into the story, as a sequence including a flood and subsequent rebuilding of rafts was shot.[3]

The camera used to shoot the film was stolen by Herzog from the Munich Film School. Years later, Herzog recalled:

"It was a very simple 35mm camera, one I used on many other films, so I do not consider it a theft. For me, it was truly a necessity. I wanted to make films and needed a camera. I had some sort of natural right to this tool. If you need air to breathe, and you are locked in a room, you have to take a chisel and hammer and break down a wall. It is your absolute right.”

To obtain the monkeys utilized in the climactic sequence, Herzog paid several locals to trap 400 monkeys; he paid them half in advance and was to pay the other half upon receipt. The trappers sold the monkeys to someone in Los Angeles or Miami, and Herzog came to the airport just as the monkeys were being loaded to be shipped out of the country. He pretended to be a veterinarian and claimed that the monkeys needed vaccinations before leaving the country. Abashedly, the handlers unloaded the monkeys, and Herzog loaded them into his jeep and drove away, used them in the shot they were required for, and released them afterwards into the jungle.

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