Because Caesar inherited his mother's genes, he had high wisdom since he was a child and lived happily with the Will family. After seeing the effect of Caesar's experiment, Will injected the same medicine into his father's body together with Alzheimer's disease, which miraculously restored his brain function. But a few years later, Will found that the human body developed antibodies to this virus drug, and Will's father's condition deteriorated. Will showed his boss the results of the drug, asked for an experiment with a more violent virus, and succeeded in the orangutan experiment. Will brought drugs home. After an accidental injury to mankind, Caesar was forced to separate from Will and was sent to a nursing home. There he was treated mercilessly, and then he became hostile to human beings. With great wisdom, Caesar successfully escaped from the nursing home, returned to Will's home, stole the medicine, took it back to the detention center for other chimpanzees to use, and began to lead them, eventually leading other chimpanzees out of the detention center. At this time, it has been proved that this drug is a deadly virus to humans, but it is harmless to orangutans and can greatly improve their wisdom. The virus has begun to spread, the situation is reversing, and a war that has to be fought against mankind is about to begin.