Bizarre murder cases where young girls' vital essence is continuously drained occur one after another in Luoxia Town. Chu Molan and Qi Yuan investigate clues, accidentally getting entangled in a conspiracy in the capital. The two receive an imperial decree to enter the capital, discovering the case involves Western Regions Wuxiang Flower poison, and Fu Jinghong is secretly harmed and poisoned. As the investigation deepens, the truth of the fake emperor borrowing a human skin mask to usurp the country is uncovered, and various factions maneuver and play games. Finally, a palace coup breaks out, the treacherous and wicked are executed, Qi Yuan becomes regent, Chu Molan gives birth to a young son, and at this time new clues of searching for the former emperor's surviving son arrive.