One of the twins of Longcheng warlord Xiao Zonghai was captured by bandits and fell off a cliff. He was picked up and raised by Shi Laodie, and was separated from the Xiao family. Many years later, the Wang puppet government was established in Nanjing. The Japanese puppets raided Shijia Village and killed Shi Laodie. The separated child Shi Shanlai grew up and decided to avenge his father and join the New Fourth Army. Liu Xiuchun, the section chief of the New Fourth Army, asked Shi Shanlai to play the weak traitor Xiao Jiuchuan who looked exactly like him, and sneak into the Xiao family to get the secret plan of the Japanese puppet commander Huang Lingling. In order to complete the task, Shi Shanlai, a grassroots man with a carefree personality, overcame all kinds of difficulties and dangers, and gained the trust of the Xiao family with outstanding strategies and courage. He approached the cunning and treacherous Commander Huang and saw through the secret of the Japanese army's launch of bacterial warfare. At a time of national crisis, Shi Shanlai accidentally recognized Xiao Zonghai and his son, persuaded the Xiao family to fight against Japan together, led his partners and the people of Longcheng to capture Longcheng, and cracked the Japanese puppet invasion plan to capture Chongqing and establish a bacterial laboratory. After a series of struggles, Shi Shanlai grew from a grassroots man to a resourceful commander of the New Fourth Army and became a true anti-Japanese hero.