Davis Okoye, a primatologist, nurtures a deep connection with George, an exceptionally intelligent silverback gorilla under his guardianship since infancy. A disastrous genetic experiment, however, transforms George, along with a wolf and a reptile, into colossal creatures. As these mutated beasts unleash havoc, Okoye joins forces with a disgraced genetic scientist and the military to acquire an antidote, thwarting a worldwide catastrophe.