Isolde, eldest daughter of the Viscount of the North Sea, and her younger sister Cecilia are reborn together on the morning of the Sea God's Blessing Day. In their previous life, Cecilia drew the golden light lot but ran away from marriage because it matched a fisherman; she wandered and suffered for years, and when she returned, her sister had become a duchess. Consumed by jealousy, she stabbed her sister at the Sea God Festival and then killed herself. After rebirth, Cecilia snatches the white light lot first and marries Aldric West, smugly believing she has stolen her sister's good fortune; the golden light lot falls to Isolde, and it still matches the same fisherman. The whole city mocks her, her father cuts ties, her mother gives her cold looks, and her sister sneers. Isolde calmly walks to Aegir by the broken fishing boat at the dock and says, "The Sea God has pointed you to me." The two marry by the sea with the Sea God as witness. After marriage, Isolde lives in a shabby seaside hut, fishing and drying nets to support herself; Cecilia is trapped in the duke's household infighting, while Aldric is cold and selfish. The temple keeps sending supplies to the dock—all secretly arranged by Aegir—but Cecilia mistakes it for the temple favoring Aldric, repeatedly intercepts the goods, and publicly humiliates Isolde. The Sea God statue trembles and glows twice, issuing the oracle, "Who gave you permission to touch my wife?" Everyone kneels, but no one sees Isolde shielded by golden light. Cecilia colludes with abyssal kin, releases a sea monster at the Sea God Festival, and frames Isolde as a follower of the evil god. Isolde is bound to the pyre; as the flames rise, the sea explodes—Aegir's golden phantom rides the waves, extinguishes the fire with heavy rain, crushes the sea monster, exposes the abyssal powder in Cecilia's sleeve, and the archbishop has her thrown into the dungeon. Isolde thinks the phantom's profile resembles her husband but dares not confirm it. Cecilia escapes the dungeon and uses Isolde's blood to break the abyssal seal. The evil god emerges; Aegir fights in his true Sea God form, repels the evil god, but his divine power is exhausted and his figure fades. Isolde kneels at the altar and prays; the whole city kneels and cries, "Please bring the Sea God back," and their faith gathers as golden light, restoring Aegir to physical form. In the end, Cecilia is imprisoned for life, her soul forever fallen into hell; Aldric is stripped of his title and imprisoned for life; Edmund and Margaret are stripped of noble status and exiled from the North Sea. Isolde and Aegir remain in the mortal world as fisherman and fisherwife, guarding the North Sea together.