As the novel’s antagonist, Dr. Moreau acts as Prendick’s antithesis. Like Prendick, he is a biologist and a brilliant one at that. But Moreau’s defining quality is his lack of morality. This amorality manifests itself in the nature of his work, which involves modifying animals through the practice of vivisection. Although vivisection inflicts unthinkable pain on his animal experiments, Moreau heartlessly discounts this pain as irrelevant. He insists, reductively, that pain is merely a physiological phenomenon that has outlived its evolutionary purpose, and therefore has no moral significance. Moreover, he pursues his work without any concern for the greater good. He obsessively pursues his goal of transforming an animal into a human, driven only by his own scientific curiosity and vanity. 

In many ways, Moreau plays the role of a god on his island. He is the creator of the island’s inhabitants, whom he has attempted to make in his own image, and he has devised the Law that forms the basis of their religion. However, as gods go, Moreau is a remarkably cruel one. When his creations inevitably disappoint him by exhibiting animal behaviors, he rejects them, casting them out to live in the jungle and threatening them with torture should they break his Law. Moreau’s death at the hands of the puma, his latest creation, illustrates the hubris of his playing-at-god. His attempts to overrule nature end in abject failure.