Tells the story of the Japanese, puppet, and Communist Party infiltrating each other during the Anti-Japanese War in 1940, and Nanjing folded into an adult hell. CCP ace agents Jin Shen Shui and Lin Ying Ying and a group of dedicated agents. In Nanjing in 1940, various forces were intertwined and internal fighting continued. With family sorrows, Jin Shen Shui and Lin Ying Ying join forces for survival. In the process of self-protection, they discovered the brutal "Spring Thunder Plan" of the Japanese army. In order to protect their homes and defend the country, the two of them walked on the tip of a knife with a mortal heart.