Martin Bond had an intriguing theory of Cosmic Descent, believing that the first intelligent life in the solar system evolved on the Moon, with the Selenites later migrating to Mars, after they had destroyed their civilization and the Moon following the discovery of atomic power. The Martians had subsequently fallen victim to the same cycle of events, and their survivors had fled to Earth. There is something inherent in the atom which is released along with nuclear energy that stirs the baser passions of living beings. And now, humanity stands on the brink of atomic warfare...