Primatologist Davis Okoye stocks an unshakable bond the intelligent, with George gorilla that has been . But this tender ape is mutated by a genetic experimentation gone into a raging creature of size. It discovered there are other animals that were similarly shifted, to make things worse. These newly generated alpha predators split across North America, destroying everything in their path, Okoye teams using a parasitic genetic engineer to secure an antidote, fighting his way via an everchanging battle, perhaps not only to halt a world wide tragedy except to save the gruesome creature which was once his pal.