The wild riders of Saim-Hanna are renowned for their skill and courage, especially their headstrong leader Nuada Fireheart. While aiding Yvraine's comrade—an emissary of the Whispering God Ynnead—he accidentally awakens a dormant threat, the Necrontyr Tomb World. Now the Fiery Heart clan is forced to enter into an alliance with the Ynnari in order to eliminate the danger to their native artificial world and thereby preserve the honor and future of the family. So the two armies return to the planet Agarimethea, intending to destroy the Necrontyr crypt before they gain strength and cannot be dealt with. But for what other purpose does Yvraine accompany Nuada and his kin, and what is her interest in relation to Niall, the sick leader of the Fireheart clan?