In her previous life, Shen Yunxi, the legitimate daughter of a great general, trusted the wrong man, the scoundrel Lin Ce, and accidentally injured Canglan, the Merman King. Her family was destroyed, and both she and Canglan met tragic deaths. Reborn, she finally sees the truth. She immediately breaks her bond with Canglan, swears a blood oath to devote herself to him for life, and tears apart the scoundrel's schemes. Together, they thwart the countless conspiracies of Lin Ce and Prince Duan, who covets the precious merman pearl. They clear their names before the imperial court and establish a maritime trading company to compete against their enemies. When their adversaries launch a palace coup and use the Sea-Burning Cauldron to slaughter the merfolk, Canglan transforms into a silver Yinglong dragon to quell the rebellion and slay their enemies. Afterward, Canglan is bestowed the title of Prince of the Eastern Sea. Shen Yunxi lets go of worldly wealth and power, travels to the depths of the sea to marry him, and vows to remain by his side for all eternity.