Diane (Sigourney Weaver Sigourney Weaver) is a wildlife expert who specializes in chimpanzees. In order to better observe and approach chimpanzees, Diane sneaks into the primeval forest in the Fran Mountains of Rwanda in Africa. Chimpanzees are ferocious and wild, which means that Diane's life could be lost every minute of being around them. With the passage of time, the distance between Diane and chimpanzees is getting closer and closer. by imitating their calls and habits, Diane gradually won the trust and affirmation of the chimpanzee community, and found a lot of valuable information and materials. Poachers were rampant in the primeval forest, and Diane struggled with them all her life, so she made many enemies. One day, her body was found in Diane's room. The evidence shows that the great scientist died of murder.