High above the Earth, the starship Basilica orbits. On board the huge vessel are a sleeping woman and an artificial intelligence, the Oversoul of Harmony, returned at last to its planet of origin. Of those who made the journey, Shedemei alone has survived the hundreds of years since Earthfall and the return of the children of Wetchik to Earth.
Shedemei and the Oversoul have recorded much of the history of Earth since they came. But in all the long years of watching and searching, the Oversoul has not found the thing it sought across the light-years from Harmony to Earth. It has not found the Keeper of Earth, the central intelligence that alone can repair the Oversoul's damaged programming and allow it to return to Harmony.
But on the planet below, among the people there, Shedemei and the Oversoul can see the influence of the Keeper. And now, in Shedemei's dreams, the Keeper speaks to her again, sending powerful warnings. She is needed on the surface below, with her knowledge and the power of the Starmaster's Cloak. And so at last she determines to go. The last living child of Harmony will return to Earth and search for the Keeper as she once searched for the Oversoul - by being its servant until at last they come face to face. (Google Books Summary)