Xie Qingci is the spiritual girl who guards the mountain in Yunhuang. She has a destiny - when she is emotional, her spiritual power will be exhausted and her soul will be scattered. She has been alone for hundreds of years, just to guard the barrier and protect the people of the three realms. Until Xie Linyuan, the banished immortal who strayed into Yunhuang by mistake, appeared, they fell in love at first sight and saved each other. Although we love each other deeply, we dare not get close to each other; if we stay together, we will die. Unexpected changes occurred in the wilderness, evil spirits were in chaos, and people on the border were killed. If she becomes emotional, all life will be destroyed; if he goes against the will of heaven, the world will be catastrophic. There are no misunderstandings, no conflicts, only the dilemma of fate. She protects the common people with ruthlessness, and he protects her with immortality. The most painful thing in this world is never separation, but - Yunhuang only allows common people, not deep love.