The underworld’s soul-reaping envoys, Black and White Impermanence: the elegant, composed Xie Bi’an and the stern, unsmiling Fan Wujiu, are ordered to investigate a bizarre murder in the mortal world. The souls of the living have failed to reach the underworld, a ghost constable has been brutally murdered, and strange silver powder and demonic aura remain at the scene. The clues point to the ancient fallen god Ye You Shen. As their investigation deepens, the two discover that the case is tied to the “Rebellion of the Two Impermanences,” a conflict the underworld deliberately buried three hundred years ago. As fragments of memory fall into place, they realize their past-life bond runs far deeper than they imagined: Xie Bi’an is the reincarnation of the White Impermanence, whose soul was scattered, while Fan Wujiu is a copy of the Black Impermanence, his memories erased. And the mastermind behind it all is none other than Ye You Shen, who lured them into tragedy all those years ago! On the day yin and yang converge, the gates of the underworld are about to fall, and countless evil spirits are poised to strike. Can Black and White Impermanence let go of their grievances and unleash the ultimate Yin-Yang Judgment once more through the power of their soul pact?