The original Charlton Heston classic.
A team of human space explorers land an a planet, the planet seems desolate but habitable, they explore their environment and find other humans, they seem like cavemen compared to them, then a hunt occurs after a hunt the humans and Taylor (the astronaut) are captured by what appears to be intelligent apes, humans on this world are mute and primitive and as he has been injured during the hunt he is unable to communicate to the speaking apes that he is intelligent as they are.
When they get back to the ape city, the ape scientists take an interest in Taylor, he tries to communicate with the scientist Zira who is convinced he is intelligent as he mimic's her actions, this pleases her and decides to put him in a partner a female called Nova.
Later Taylor steals some pen and paper from Zira and this convinces her of his intelligence, Zira enlists her partner Cornelius to help and with written communication he tells Zira and Cornelius where he came from, then Cornelius's boss a Dr. Zaius as learns of Taylor's intelligence but thinks this as some sort of sideshow mimicked intelligence and orders him to be castrated, Taylor tries to escape and during the escape speaks uttering the films probably most famous lines.
The Apes then have cause to take Taylor seriously but refuse to believe his stories of space travel and threaten to labotomize him, he tells them of others that came with him but he later finds one was killed and the other has been labotomized.
Taylor with help from Zira and Cornellious and other apes that believe in fair treatment for humans manages to escape taking Nova with him and also kidnap Dr. Zaius building up for a dramatic ending.
The film is a stone cold classic, and is filled with many memorable scene's but tends to drag in places and for me has too much plot build up in places.