Gordon R. Dickson’s “Childe Cycle” of novels depicting the future of the human race has been one of the grand epics of science fiction. At the time of his death in 2001, Dickson was writing Antagonist, the tale of Bleys Ahrens’ turn toward darkness. Now Dickson’s assistant David W. Wixon has brilliantly finished the long-awaited book, working from Dickson’s copious notes. Antagonist is a fitting capstone to one of the most ambitious series in SF history.   The Childe Cycle is the story of a new human evolution: the development of a real, hardwired sense of “responsibility” shared by all human beings. Donal Graeme was a Dorsai, a mercenary soldier, and also a mutant gifted with insight into the path forward for the human race. Through his gifts Donal would come to bend time and live three lifetimes—and, in the process, run into problems he had not expected: first, his own flaws, and second, the existence of another mutant, Bleys Ahrens.   Following Young Bleys and Other, Antagonist advances the story of the formidably powerful Bleys Ahrens. Bleys is a man with a clear vision of the struggle in which he’s involved -- but an increasingly deficient sense of human values. He and his organization, the Others, are tracking down an elusive interplanetary opposition. Meanwhile, Bleys' own intricate conspiracies and devisings, and his quest for power, which began with the best of motives, have become something darker and fiercer.   He's committed to his plans. They may bring about the advent of Homo superior. And they may destroy the human race.