Description:  Return to the Planet of the Apes is a 1975-1976 animated Saturday-morning series about three astronauts who are sent through a time vortex and crash-land on a future Earth ruled by intelligent apes. The show, which features a continuous storyline, drew from the novel and the first two films, featuring characters like Cornelius, Zira, and Dr. Zaius, along with a gorilla named Urko, who is based on the character from the live-action TV series.

The premise: Three astronauts—Bill, Jeff, and Judy—are caught in a time vortex and arrive on Earth in the year 3979, where apes have become the dominant species.

Human and ape characters: They encounter familiar ape characters like the scientists Cornelius and Zira, and the conservative leader Dr. Zaius, alongside a gorilla security chief named Urko. They also meet a human named Nova, who wears the dog tags of Brent from the movie Beneath the Planet of the Apes.

The storyline: Judy disappears during an earthquake, and Bill and Jeff seek refuge with a colony of primitive humans, becoming fugitives from the gorilla army.

The mutants: A group known as the "Underdwellers," a nod to the mutants in Beneath the Planet of the Apes, are responsible for earthquakes and walls of fire in the Forbidden Zone.

Content restrictions: NBC's "Emulative Clause" limited the series by forbidding apes from using firearms like machine guns, knives, or pistols. However, they were allowed to carry rifles, though they couldn't use them, and howitzers were permitted.