In 1937, Tong Jiaru (played by Yang Zhigang), a native of Rehe, left his hometown to teach Chinese at Nie Zhongcheng Middle School in Shanghai. His adopted daughter Nannan became disabled, and he was forced to stay when he wanted to flee south again. Witnessing the invaders killing his compatriots, he swallowed his anger and only wanted to save his life. Student Ouyang (played by Zhang Jiayi) served the country and urgently needed an assistant. Tong Jiaru bit the bullet to help. Ouyang died, and Tong Jiaru was exposed and targeted by the Japanese spy Dongcun. He cleverly completed the task and got rid of suspicion. Ouyang's boss Yang Xiao was arrested, and Tong Jiaru rescued him. His wife Zhizi had just given birth to her son Xiwang, but was killed for protecting Yang Xiao. In half a year, the four murderers who participated in the murder of Zhizi were all killed by Tong Jiaru without revealing their feet. Dongcun suffered from the lack of evidence and tried to force Tong to confess with cruel torture instruments. The Communists organized teachers and students to march and rescued Tong Jiaru. Three years later, Tong Jiaru used himself as bait to help comrades from the Kuomintang and the Communist Party to jointly eliminate the Japanese spy base. The Japanese surrendered, and Dongcun kidnapped Xiwang and forced Tong Jiaru to duel with him. His comrades subdued Dongcun and rescued Xiwang. Dongcun cursed Tong for being a coward, and Tong Jiaru told him: "Chinese people have a brave heart when facing invaders.