This story by Arthur C. Clarke takes the form of a radio message from a group of aliens in an approaching spaceship, assuring the people of Earth that they have nothing to fear. The visitors claim to share a common ancestry with man, both being descended from an advanced race who colonized Earth during the time of the dinosaurs. Those who could fled when a genetic plague caused division, conflict and savagery among the population. They are returning with a cure for any who might still be affected. Themes include climate change, escape, reunification, evolutionary divergence, racism.
