[2][3] In the novel, "young" humans (recreations of the medieval originals) are transported through the Big Collapse, at the end of time, to seed the next cycle of the universe.

The habitats are protected and uncoupled from the universe's entropy by means of force fields projected by giant obelisks.

In the human realm, these are inscribed with the recorded history of humankind, sorted chronologically from the bottom up, including the science that went with it.

A legend tells the protagonist that his beloved (frozen in stasis) will awaken if he goes on quest to the rim walls of the habitat, and he does so.

He makes contact with an artificial intelligence guardian of Hegira, who tells him the story and advises him to go and populate the new universe since he has become part of the last one.