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As the grandmaster who founded the Demonic Sect, Wei Wuxian roamed the world in his wanton ways, hated by millions for the chaos he created. Ultimately, he met his end at the hands of his dear adoptive brother, Jiang Cheng. Over a decade later, he finds himself incarnated into the body of a lunatic and runs into a former classmate, Lan Wangji. The two men with opposing personalities delve into the mysteries of spirits and ghosts, while Jiang Cheng suspects that Wei Wuxian has returned.