The fourth and culminating volume in Julian May's dazzling quartet of science-fiction novels brings to a climax the struggle for the Many-Colored Land--the Earth six million years ago--and completes the series that has become an international best-seller and multiple award nominee. Human time-travelers from the sophisticated Galactic Milieu of the twenty-second century came to the Pliocene Epoch seeking a Garden of Eden. What they found was slavery under the knightly Tanu race, who had been exiled to Earth from a far galaxy. Freed by the usurper Aiken Drum, the humans enjoy a brief period of dominance. But now King Aiken's rule is threatened by the dwarfish Firvulag, who scheme to destroy both humans and Tanu in the nightfall War, a ritual Gotterdammerung that had been postponed when Tanu and Firvulag were banished to Pliocene Earth. This menace becomes almost incidental when Aiken discovers that his realm is about to be invaded by another human who possesses metapsychic powers even greater than Aiken's own. He is Marc Remillard, the Adversary, instigator of the Metapsychic Rebellion, who nearly conquered the Milieu, and then fled through the time-gate after his defeat. Marc and his surviving followers come against Aiken when it seems that a new time-gate is about to be built--one that will provide a two-way portal between the Many-Colored Land and the future world of the Milieu. "The Adversary, "like its predecessors "(The Many-Colored Land, The Golden Tore, "and "The Nonborn King), "combines science and fantastic imagery with rousing adventure, humor, and an optimistic view of the human character as it contends against mental and physical perils.