Many years after the reign of Caesar, a young ape goes on a journey that will lead him to question everything he's been taught about the past and make choices that will define a future for apes and humans alike.

When a massive sinkhole mysteriously opens in Los Angeles, it tears a family in half, separating mother and son from father and daughter. When part of the family finds themselves in an unexplainable primeval world, alongside a disparate group of strangers, they must work to survive and uncover the mystery of where they are and if there is a way back home.

When they learn of a secret plot to track and control kids, identical twins Dru and Kal team up with a band of runaway rebels to take back their world.