With secret aid from ComStar—the Terran-based sect that serves as the keeper of the Inner Sphere's technological secrets and controls interstellar communication—the Clans' BattleMech warriors have been incredibly successful in their campaign of invasion. But ComStar has its own reasons for giving aid to the enemy, and if its strategy proves successful, the Inner Sphere worlds will be finally be reunited under ComStar's rule.
Yet neither the Clans nor the Great Houses of the Inner Sphere are ready to become ComStar's puppets. And within ComStar's upper echelon a new power struggle is about to begin. As the Clans continue their inward drive, with Terra itself as their true goal, can ComStar mobilize the Inner Sphere's last defenses—or will their own internal political warfare provide the final death blow to the empire they are sworn to protect?