Foundation and Empire is the story of humanity's perpetual struggle against the darkness that forever threatens to overwhelm the light and of how the courage of even a determined few can make all the difference in the universe. Led by its founding father, the psycho-historian Hari Seldon, and utilizing science and technology, the Foundation survived the greed and barbarism of its neighboring warrior-planets. Now cleverness and courage may not be enough. For the Empire—the mightiest force in the Galaxy, is even more dangerous in its death throes. Even worse, a mysterious entity called the "Mule" has appeared with powers beyond anything humanly conceivable. Who or what is the "Mule"? And how is humanity to defend itself against this invulnerable avatar of annihilation?--