In this sequel to The Guardians, Maxine, the Qatar family, a scholar of antiquities, and three mysterious sisters of the stone travel through time to Egypt 2900 BC, in an attempt to find ancient Guardians they believe came to Earth and built a planetary weapon array. Their mission is to locate the engineer of this ancient weapon so that they can return him and themselves to modern Earth and re-activate the array to use against the imminent attack of a second swarm. Almost immediately, Maxine and company are repeatedly threatened and in conflict with the ancient Guardians they encounter in the past who now call themselves Ra, Osiris, and Baal.After Osiris attempts to have them killed, Maxine and her companions are forced to flee Egypt, but not before Ra reveals to them that a Guardian named Atlas is the one they must find, as he designed the weapon they seek. In this effort to locate Atlas our travelers go to Greece, and with the help of Baal, they enlist the aid of Poseidon and his Nereid wife, Amphitrite, to create a strategy that could free Atlas from his imprisonment by the reviled Zeus.This plan requires Maxine and company to engage with yet another Guardian, Leto, and her crew of Titans, and to insert themselves into the aftermath of a civil war while lies, sabotage, and an active volcano threaten to undo everything. Will Maxine and her Guardians succeed, or will they all become trapped in the past and leave Earth defenseless against final annihilation?