The fourth volume in Cherryh's Fortress cycle finds TristenAcreated by the wizard Mauryl to combat the power-crazed, undying spirit of the dark sorcerer Hasufin HeltainAsent back to Amefel as its duke, replacing the dishonored Orien Aswydd. Orien was cast into exile with her sister, Tarien, for betraying her oaths as duchess, and for colluding with Hasufin. But now Orien and Tarien, who is eight months pregnant with King Cefwyn's bastard child, are making their way through a supernatural storm to return to Amefel. Back in the capital, Cefwyn and his foreign bride, Ninevrise, are plotting a war, which is getting complicated by their many enemies and the kingdom's dual religious practices, as well as by the general populace's distrust of Ninevrise (because they believe she subscribes to the wrong religion and suspect that she may partake in heinous magical practices).

It started long ago, as a war between the shadowy Immortals that persists today, as the wizard Mauryl's Shaping confronts the Shadows summoned from Chaos. Tristen is that Shaping. Both more and less than human, he successfully fought sorcery's evil tides, a victory that brought his friend

Cefwyn both a kingdom and true love. But the Lines that hold the world in place are shifting again. A ruthless enemy is preparing for battle. Once again, Tristen will take up the sword inscribed with "Truth" and "Illusion" on its blade. But he faces more than war and a pretender to Cefwyn's throne. The Shadows he sees are straight from Ruin--a flow of darkness covering the world like ink...