In 1942, when the Anti-Japanese War was at its peak, the Japanese army raided an arsenal of the New Fourth Army in the northern region. The independent regiment's special agent company defending the arsenal fought bloody battles, but was outnumbered and lost its position. The company commander Kong Yuan was captured. Kong Yuan's brother Kong Fang is a university mathematics professor who is proficient in mathematical logic analysis. He studied in Japan and had some understanding of the situation of the Japanese army. With the help of the New Fourth Army, Kong Fang and his fiancée, psychology professor Xiang Haiyin, sneaked into the Japanese-occupied area, launched a counterattack, successfully rescued his brother and the arsenal personnel, and recaptured the position. This drama is based on the defense of the Huangyadong Arsenal and many arsenal deeds, and uses the deeds of ordinary people to show a vivid historical picture of people from all walks of life uniting to fight the war.