Fourth in Card's series (The Ships of Earth, 1993, etc.) about the inhabitants of planet Harmony, whose ruling computer, the 40-million-year-old Oversoul, is breaking down. Nafai the Navigator and his extended family, bred, trained, and recruited by the Oversoul, have assembled a starship and now head towards Earth, hoping to find assistance. During and after the voyage, problems arise through Nafai's refusal to kill his murderous, vengeful brother, Elemak. Earth, they discover, is ruled by an Oversoul-like Keeper and inhabited by two mutually dependent races, the winged angels and the subterranean diggers. Eventually Nafai will pass his navigator's cloak to Shedemei, in order to found a new community where the three species may dwell together in peace. Card's series would be more reader-friendly with fewer characters, and if the individual entries were more self-contained. Nevertheless, it continues to impress.