Many generations after Caesar’s death,[a] the apes have split into numerous clans. Noa, a chimpanzee of an eagle-oriented clan, prepares for a coming of age by collecting eagle eggs with his friends Anaya and Soona, the latter of which he is infatuated with. However, a human inadvertently cracks Noa’s egg, which results in him heading back to the city to find one. That night, he discovers members of a rogue clan that serve Proximus Caesar, who leads with a twisted version of the original Caesar’s teachings. After they discover Noa’s horse, they use it to head to his clan. By the time he gets back, his home is ablaze. As he tries to save his father, Koro, from the blaze, Proximus’ general Sylva kills Koro in front of Noa.

Noa awakes some time after, discovering his family is taken and his father’s corpse with Koro’s eagle lingering behind. Noa buries Koro and searches for his family. In the remains of an LAX terminal, he encounters an orangutan named Raka who tells Noa the real teachings of Caesar. He notices the human stalking nearby and offers food and a blanket, naming her Nova. During their journey, they encounter other humans. Noa decides to leave and insists Raka stay behind with his teachings. However, Proximus’ clan attacks the humans, causing Noa to have a change of heart and rescue Nova, who later reveals her name to be Mae. She tells Noa where Proximus took his clan, believing he settled near an old human bunker.

On their way to the settlement, they are trapped while trying to cross a bridge over a river. In the ensuing fight, Raka comes to Mae’s aid but is himself washed away by the current and drowns. Noa and Mae are taken to Proximus’ camp, where he reunites with Soona and his mother. Proximus reveals himself and invites Noa to a dinner with Mae and Trevathan, a human who allied himself with the apes. He believes Noa to be useful, and demands to know what Mae’s plan is, advising Noa that she only wants to benefit herself.