Conquest of the Planet of the Apes is a 1972 science fiction film directed by J. Lee Thompson and written by Paul Dehn. It is the fourth of five films in the original Planet of the Apes series produced by Arthur P. Jacobs. The film stars Roddy McDowall, Don Murray and Ricardo Montalbán. It explores how the apes rebelled from humanity's ill treatment following Escape from the Planet of the Apes (1971). It was followed by Battle for the Planet of the Apes (1973).