Filming and production started for the third installment in the original Planet of the Apes series.
Screenwriters and the production team developed the storyline and script for the movie.
Cornelius and Zira, two intelligent apes from the future, escape the destruction of their civilization by traveling back in time to 20th century Earth.
Cornelius and Zira arrive in Los Angeles, 1973, causing a sensation as talking apes in a human society.
Dr. Hasslein examines the apes and confirms their intelligence and origin from the future, raising concerns about the impact on humanity's timeline.
The apes become media celebrities, facing both fascination and hostility from the public and government authorities.
The government detains Cornelius and Zira for further study, fearing the implications of their presence and future knowledge.
Faced with the threat of his knowledge altering history, Dr. Hasslein plots to kill the apes to prevent the apes' future domination over humans.
Zira is killed while trying to escape with Caesar; Cornelius is killed as well, leaving Caesar as the sole surviving member of his family.
After the death of his parents, Caesar is taken in and secretly raised by humans who recognize his potential.
