For nine hundred years, seven royal houses have controlled the necessities of civilization through the Concord, an alliance designed to prevent any crown from becoming too powerful. After the Queen of Avarra is murdered, her daughter Seraphine discovers that her kingdom was meant to hold an erased eighth seat, granting authority over every throne. King Kael of Veyr offers marriage, armies, and proof that the Concord ordered the assassination. Both rulers secretly intend to seize control of the system, but their alliance becomes dangerous when their growing love forces kingdoms to choose between the old order and a united pair powerful enough to remake the world.