内容简介：After years of bitter struggle, Trantor had at last completed its work—its Galactic Empire ruled all 200 million planets of the Galaxy . . . all but one. On a backward planet called Earth were those who nurtured bitter dreams of a mythical, half-remembered past when the planet was humanity’s only home. The other worlds despised it or merely patronized it—until a man from the past miraculously stepped through a time fault that spanned a millennium.