Conquest of the Planet of the Apes is the fourth installment in the Planet of the Apes series. In 1991, Caesar (Roddy McDowall), the son of time-traveling apes Cornelius and Zira, has grown up under the protection of a circus owner, Armando (Ricardo Montalban). Unlike other primates on the planet, Caesar has the ability to talk and communicate. As he watches the humans turn his primitive brothers into pets and then slaves, he becomes outraged at the treatment of these chimps. When he reveals his powers of speech in a confrontation with the military, Armando is killed. Caesar, no longer content to watch the suffering of other apes, launches a revolution against the human oppressors. He teaches them combat and how to use weapons. They gather and revolt against Ape Management, with the apes showing they can be just as inhumane as their human masters. The 1972 science fiction film was directed by J. Lee Thompson.