In mythology, there is the land of Yunhuang, where the three major tribes of Kongsang, Quanxian, and Cangliu have lived for generations. Seven thousand years ago, Kongsang Star honored the king and imprisoned the spring dragon god, forcing the mermaids to live only on the earth and not return to the Biluohai where they had lived for generations.

Ruyi recognized Su Ge as the young master of the Sea Emperor, but Su Ge refused to leave. Huangtian recognizes his lord Zhenlan, and Zhenlan officially becomes the Crown Prince of Kongsang. Bai Ying was also conferred the title of Crown Princess by King Kong Sang Chengguang, but she did not want to marry an unfamiliar Crown Prince. Her wish was to defend her country.

Exiled Crown Princess Bai Ying reconnects with Su Mo, a former slave turned servant in the Mirror Tower. Amid political turmoil, Su Mo is torn between duty to Qing Wangchen and his love for Bai Ying. As tragedy strikes, their bond faces impossible choices in a world on the brink of destruction.

Su Mo resigns from his position to avoid Bai Ying, but they meet at the library, becoming friends. Zhen Lan’s jealousy grows, and Su Mo, torn between duty and love, saves Bai Ying from a poisoned wound. Before leaving, he gifts her blooming snow cherry blossoms, and they both attend the Flower God Festival.

Su Mo and Bai Ying’s bond grew as they evaded Qing Wangchen, but Bai Ying’s seal was broken, and she was taken back to the tower. Accused of eloping, Bai Ying leapt from the tower to protect her family. A hundred years later, Su Mo returns, and Cangliu’s threat intensifies.

Na Sheng, with the Huangtian Ring, learns of Zhen Lan’s identity and agrees to deliver the imperial ring. Meanwhile, Su Mo and Bai Ying reunite, but she rejects him. Cangliu pursues the ring's bearer, and Na Sheng, Su Mo, and Zhen Lan face danger while searching for answers in Tianque Temple.