Late winter. Phagors are dominant. Most Humans live in primitive hunter-gatherer tribes, the few civilised areas are governed harshly. Yuli and his father Alehaw travel far from their family to hunt during an annual migration but are attacked by Phagors and Alehaw is taken as a slave. Yuli wanders south seeking food and shelter, he eventually comes to Pannoval, a theocratic city in a giant cave system. Yuli comes to be a part of the ruling priests but falls in love loses faith, eventually fleeing Pannoval with a small party of heretics. They emerges on the surface, where the climate is becoming mild enough for them to survive and soon come to rule first one settlement, then another. Spring breaks and everybody gets Bone Fever. The settlement's head start with the superior culture that the original party brought enables it to grow rapidly in size and power as human civilisation reappears on the surface. The rest of the book follows Yuli's decedents who live in Embruddock in the face of a Phagor migration.
