In this third installment of the Planet of the Apes series, Cornelius (Roddy McDowall), Zira (Kim Hunter) and Milo (Sal Mineo) travel back in time to escape the destruction of their world. Landing in 20th century Los Angeles, they're treated as curiosities and celebrities at first, but soon become hunted by a suspicious and fearful government intent on making them the subjects of an experiment that could alter the course of human and ape events.