Astronauts Alan Virdon and Peter Burke leave Earth on a deep-space mission in 1985. They inadvertently pass through a timewarp and return to Earth, but find that they have jumped 1,100 years into the future. Apes have now evolved intelligence and speech and are the predominant lifeform, keeping the uncivilized humans as slaves. The apes know that human kind almost wiped itself out in nuclear war and are afraid of any technology more sophisticated than guns.

Alan and Pete are quickly captured by the ruling authorities but catch the interest of a intelligent young chimpanzee scientist, Galen. With his help they escape and now roam the Planet of the Apes trying to find a way to tap into the navigational disk from their ship's computer and find a way back to their own time.

The three travel the lands helping humans in need with the aid of their advanced knowledge. They're hunted by General Urko, a gorilla and a military commander, who is in an uneasy alliance with Doctor Zaius, an orangutan elder who seeks to suppress all technology and make sure the apes maintain their supremacy... while fearing that the astronauts may bring back the wars that almost destroyed Earth the first time.

(l to r: James Naughton, Roddy McDowell, Ron Harper)