The Alterran planet is near its end. Its underground inhabitants are near a breaking point. Should they overrun Earth? Should they resort to a digital existence? The battle for Earth is looming. En.Lil, En.Ki and their father, Anu, battle insurgents and lead their destitute human progeny—Earthlings—in establishing the first civilizations of Sumer and Egypt. (An appendix summarizes the initial three books.)