Young scientist Will Rodman is determined to find a drug that can help regenerate diseased or degenerated brain tissue. He is driven by both altruistic and personal motivations, as his father is suffering from Alzheimer's disease and is rapidly deteriorating. In order to achieve this goal, Will becomes a workaholic at a major biotech corporation, Gen-Sys, where the project is seen as a potential source of huge profits. All testing is done on chimpanzees. When a female chimpanzee whose intelligence was enhanced by doses of the experimental "ALZ-112" drug is accidentally killed, Will brings her orphaned baby home to raise as a pet. The baby, named Caesar, has inherited the uncertain virus strain genetically and is developing a near-human IQ.