Sixty years ago, the Just City schismed into five cities, each devoted to a different version of the original vision. Forty years ago, the five cities managed to bring their squabbles to a close. But in consequence of their struggle, their existence finally came to the attention of Zeus, who can't allow them to remain in deep antiquity, changing the course of human history. Convinced by Apollo to spare the Cities, Zeus instead moved everything on the island to the planet Plato, circling its own distant sun. Now, more than a generation has passed. The Cities are flourishing on Plato, and even trading with multiple alien species. Then, on the same day, two things happen. Pytheas dies as a human, returning immediately as Apollo in his full glory. And there's suddenly a human ship in orbit around Plato...a ship from Earth.