Regis Hastur, lord of the most powerful of the seven domains of Darkover, learns that the Terran Federation's operatives are pressuring Darkover to give up its closed world status and become a full member of this intergalactic empire. But Regis knows that if Darkover joins the Federation his beloved home planet will become nothing more than a military hub, sapped of its resources and cultural heritage. Still there are those among Darkover's ruling families who are tempted by the promise of increased technology that membership in the Federation would bring.

Meanwhile, Regis learns that he has an older illegitimate brother, Rinaldo. But his joy in finding his sibling is short-lived, as Regis's enemies try to force him to abdicate leadership of Darkover in favor of his older brother. They hope to manipulate Rinaldo into agreeing to join the Federation. But unbeknownst to anyone, Rinaldo has a plan of his own...