Only a few know the terrifying truth - an outcast Earth scientist, a rebellious alien inhabitant of a dying planet, a lunar-born human intuitionist who senses the imminent annihilation of the Sun... They know the truth - but who will listen? They have foreseen the cost of abundant energy - but who will believe?These few beings, human and alien, hold the key to the Earth's survival.

His name was Biron Farrill and he was a student at the University of Earth. A native of one of the helpless Nebular Kingdoms, he saw his home world conquered and controlled by the planet Tyrann - a ruthless, barbaric Empire that was building a dynasty of cruelty and domination among the stars. Farrill’s own father had been executed for trying to resist the Tyrann dictatorship and now someone was trying to kill Biron. But why? His only hope for survival lay in fleeing Earth and joining the rebellion that was rumored to be forming somewhere in the Kingdoms.

The Eternals, the ruling class of the Future, had the power of life and death not only over every human being but over the very centuries into which they were born. Past, Present, and Future could be created or destroyed at will. You had to be special to become an Eternal. Andrew Harlan was special. Until he committed the one unforgivable sin - falling in love. Eternals weren’t supposed to have feelings. But Andrew could not deny the sensations that were struggling within him. He knew he could not keep this secret forever. And so he began to plan his escape.

They mustn't harm a human being, they must obey human orders, and they must protect their own existence...but only so long as that doesn't violate rules one and two. With these Three Laws of Robotics, humanity embarked on a bold new era of evolution that would open up enormous possibilities, and unforeseen risks.

A collection of 20 classic short stories by Isaac Asimov, author of the Foundation series, featuring the definitive and only in-print version of “Nightfall”.