In a forest, an old man dressed in homespun is forced to climb up a tree when a dog attacks him. The dog’s owner shows up: a humanoid ape boy. However, a spaceship crashes near by, scaring both of them. The boy, Arno, runs away with his dog and the old man, Farrow, goes to investigate. The ship’s door open and he climbs inside to find three men: one is dead and the other two unconscious.
Meanwhile the ape boy goes to his nearby town and reports to his father, the Prefect. the Prefect goes to investigate and Farrow gets the two unconscious men to safety just before the patrol arrives. He takes them to a storage bunker and leaves for a while. The men Peter Burke and Alan Virdon, wake up and try to figure out what happened. They were on their way to Alpha Centauri and ran into a radioactive storm, and their third teammate, Jonesy, activate the return beacon to Earth. Farrow returns and they try to figure out what planet they’re on. Farrow explains that apes now rule and the humans are slaves, and has no idea what planet he is on, or that there is such a thing as other planets. After he leaves, Pete and Alan decide to check things out and runs into a gorilla patrol, but manage to escape.
In Central City 30 miles away, one of the ruling apes, the orangutan Dr. Zaius, takes on a new assistant, Galen. Galen is a chimpanzee scientist and the son of a fellow councilman. They receive word of the spaceship and they meet with Urko, the gorilla in charge of ape security. Zaius insists that Urko bring them in for questioning, because the advanced humans they captured 10 years ago were killed before they could find out anything from them. Zaius sends Galen with Urko to represent his authority and make sure the humans are brought back alive.
The astronauts get back to the cave and Farrow returns, and he shows them a book which shows that they’re still on Earth. At least 500 years ago, something happened that put the apes in control. The astronauts go back to the ship to get an exact time readout and Farrow leads off the guards while they get inside, only to find the interior stripped clean. They do figure out the time, though: March 21, 3085. They try to escape but Farrow is killed and Urko captures them. Galen examines the ship and is intrigued by the technology.
The astronauts are taken to Central City and prepare to escape when Galen enters and asks for answers. Their explanation undermines his belief in the superiority of the apes and he increases security, thwarting their escape. They are brought before the Ape Council where Zaius and the others conduct a brief kangaroo court against them which they have no way to defend themselves. Urko demonstrates a grenade he took from Zaius’ house to demonstrate how warlike the humans were. He tires to order their execution but the Council overrides him and keeps the astronauts alive for interrogation.
Galen goes to Zaius and demands to know how the humans could have been superiority. Zaius warns him against “heresy” but Galen wonders how they can treat intelligent beings as slaves. He goes to the astronauts and eventually accepts their story. The guys are interested in the grenade and want to know who developed it. Alan figures if they can recover the magnetic flight disk from the ship, they can use computer technology to recreate their flight path and return through the warp. They try to get Galen to help but he refuses to turn against his own people. He goes outside and a guard working for Urko leaves the cell door unlocked. The astronauts escape and the guard tries to shoot them on Urko’s orders, but Galen intervenes and accidentally kills the guard while the guys escape.
Galen is taken into custody and Urko accuses him of conspiring with the humans. Zaius refuses to defend his protégé, but the astronauts locate Zaius’ house and use him as a hostage, taking one of the human grenades. Zaius defends his actions, revealing that he’s aware of how the humans wiped themselves out and now the (relatively) more peaceful apes must keep the peace at any cost. They force him to take them to Galen and free the chimpanzee, using the grenade to destroy the cell door. They hide out long enough to evade Urko and his men, then go to the spaceship. They manage to get the flight disc and escape seconds before Urko and Zaius arrive to destroy the ship. Now they have to travel the countryside hoping to find someone with the technology to let them get back home. And the quest begins… Share this article with your friends