Set has been vanquished, but victory demanded a bitter price. The First Ark's detonation flung the new Ark Lords five years into the future. They emerge into a world ruled by deathless, demons, and old things that have awoken from the sleep of ages. Hades and the mysterious Grey Men have paved the way for the return of the Builders, slowly conquering the world. Only one part of their plan remains, seizing control of the Proto-Ark rumored to lay somewhere deep in the Amazonian jungle. Hades sends his demonic enforcer, Nox, once known as the Director, to claim their prize. If they succeed, the invasion of the Builders will finally begin. Only the trio of returning Ark Lords has a prayer of stopping Nox, but they face problems of their own.

Blair and Liz arrive in Northern California to find Angel Island deserted and San Francisco controlled by a kingdom of deathless. Jordan and Trevor return to Peru where werewolves have founded a new religion worshipping the Mother. A religion that preaches that Trevor is the ancient enemy, and must be destroyed. Only Jordan can save him, if he can finally learn to trust an old enemy. Win or lose, the Builders are coming. They need an army. They need The Great Pack.