Primatologist Davis Okoye shares an unbreakable bond with George, the extraordinarily intelligent, albino gorilla who has been in his care most of its life. But a mysterious genetic experiment mutates this once gentle ape into a raging creature of enormous size. To make matters worse, a wolf (Ralph) and crocodile (Lizzie) have undergone similar changes. As these newly created apex predators battle each other for supremacy, destroying everything in their path, Okoye teams with Dr. Kate Caldwell to secure an antidote. The two fight their way, to halt a global catastrophe, and to save the fearsome beast that was once Okoye's friend.