For 500 years the distant Terran colony of Corwin had no communication with Earth. But now the invincible war-horde of the Klodni was on the march and the long-forgotten planet desperately needed Earth's help. Baird Ewing was appointed ambassador, sent to get that help.
But Earth...Earth had degenerated into a decadent world of worthless pleasure seekers, and would never be able to give the aid that would save Corwin. Earth had nothing to offer, and Ewing had so little time—the answer was right under his nose if he would only look...
This is primarily a time-travel paradox story, for the solution to Ewing's problem involves a small backwards trip and a bunch of tricky thinking. A well-thought-out plot, if not especially deep. One of the more interesting tidbits is the manifestation of the 39th Century Earthers' decadence. The fashion is rather extreme body modification: elaborate piercings, jeweled studs implanted the skull, even to ears and other parts removed. An interesting prediction given today's fashions, and the oldest mention I've seen of this particular theme. Silverberg has returned many times to the possibility of humans altering their appearance.
By Silverberg's count, this is his sixth novel. As a special note in correction of some other listings: A Man Called Destiny, the other side of the Ace Double, was not written by Silverberg, but by Lan Wright, whom Silverberg describes as an British writer of unknown current whereabouts.
More recent publications of this novel have used the title Shadow on the Stars, which was the title of the short story on which the book was based.
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