O Trapalhão no Planalto dos Macacos (1976)
This movie is a spoof of "Planet of the Apes" (1968) and follows the storyline of the original step by step - in spite of being a crazy parody of the original film. A group of men lands in a balloon on an area (it's not a planet, it's more like a hill) where talking apes rule and humans are slaves.