Archaeologist Su Wanwan travels to the world of immortals due to the Dunhuang murals, and awakens her identity as a princess of the Mohe Clan in her previous life. However, she discovers that she is the host of fragments of the ancient artifact "Reincarnation Mirror" and is responsible for reversing the "blood disaster of annihilation". The cold-hearted Immortal Lord Xie Xuanxiao forcibly concluded a "life-and-death contract" to save her, sharing pain and spiritual power. As the two searched for the mirror fragments, they gradually uncovered the secret of his Demon Lord's son - the truth about the accidental killing of her in the past life, and the atonement of protecting her with his life in this life.
The human state master Xiao Chengyu secretly controls the blood contract puppet and carries out human sacrifice. He is actually the reincarnation of Tian Huan in an attempt to resurrect the ancient demon god. Su Wanwan uses modern knowledge of chemistry and physics to break through the poison test, while Xie Xuanxiao endures the suspicion of the divine realm and the backlash of the God-killing Bones. In the maelstrom of the Mo River Secret Realm, the Prajna Illusion Realm, and the Taixu Palace, the two solve the mystery of immortals and demons while repairing the bond of love and hate that spans reincarnation. When the star path map is reversed and the demon king's remnant soul awakens, a battle to change fate that combines technology and immortality begins in the cracks in the fate of the three realms...
