Aspiring young detective Xiang Li Xiqi takes on the case of a stolen research paper at school. With help from his friend Ren Shirou, he investigates a web of clues and classmates’ suspicious actions. As doubts rise, Xiang must rely on his sharp instincts to uncover the truth and prove himself.

Based on true events set during WWII in Northeast China, an ordinary man is thrust into a turbulent fate against the backdrop of the inhumane bacterial experiments conducted by the Japanese Imperial Army's notorious Unit 731.