The film recreates the process of the Chinese Communist Party's Special Operations Department, which began to fight in Shanghai in the 1920s, and fought desperately against various forces on the hidden front. It shows the irreplaceable contributions of the unknown heroes on the secret front of the party, which were indispensable in the process of victory. After the outbreak of the full-scale war of resistance against Japan, the Chinese Communist Party's Special Operations Department, led by the Chinese Communist Party, dealt with Chongqing, the Wang Puppet regime, and the Japanese spy agencies in Shanghai. Through the intricate intelligence system behind enemy lines, they instigated the enemy to defect, obtained intelligence, killed traitors, and established a broader united front until the eve of the victory of the war of resistance against Japan...