Conditions worsen for the remaining young residents of a small California coastal town isolated by supernatural events when their food supplies dwindle and the Darkness underground awakens.

As the young residents of Perdido Beach begin to better comprehend the truths of who they are and their relationships to one another, the Darkness finds a new way to be born, bringing their understanding of fear to a new level.

America is a barren landscape of smoldering ashes, devoid of life except for those people still struggling to scratch out some type of existence. Amidst the destruction, a father and his young son walk, always toward the coast, but with no real understanding that circumstances will improve once they arrive. Still they persevere, and their relationship comes to represent goodness in a world that is utterly devastated.

"Having escaped AEtheria, Aral and Rex take refuge on Cthonia near the impact site of AEtheria's power plant. At the same time, a team of armed Cthonian scouts sets out to recover their dead from the destruction. Among them, the AEtherian refugee Maire Himmel offers her knowledge of AEtheria to identify remnants of the destroyed power plant. Upon her arrival, though, Rex recognizes Maire as his mother, who was forced to leave him with a foster father...