Sword Master Shen Changning was at the peak of his ruthless practice. In order to protect the peace of his sect, he voluntarily sacrificed himself to seal the ancient demon king. However, he was betrayed by his sect and his soul disappeared. Thousands of years later, a remnant soul was accidentally reborn in the body of the mortal princess Bai Su. With her past life memories and ruthless Tao mentality, she discovered that the immortality in this world was withered and demonic energy was everywhere. What shocked her even more was that Jun Buyi, the "little apprentice" with a semi-demon physique who was once taken in and abandoned by her, had become a paranoid immortal king in charge of the demonic realm, and was looking for her remnant soul in Kyushu. Shen Changning decided to rebuild the ruthless swordsmanship, regain his strength, find out the truth about the sect's betrayal, and seek a way to escape the shackles of heaven and earth. However, Jun Buyi had a deep obsession with her and pressed on her step by step, using all means to trap her by his side and force her to face the love that had been severed. In the midst of the love-hate entanglement with Jun Buyi, the settlement of grievances with the old sect, and the many crises of resisting the invasion of demons, Shen Changning gradually regained the humanity cut off by the ruthless Tao. Finally, he entered the Tao with love, broke through the shackles of heaven and earth, and joined hands with Jun Buyi to protect the common people and protect each other's love.
