In 1938, during the Anti-Japanese War and the cooperation between the Kuomintang and the Communist Party, Chiang Kai-shek listened to slander and ordered the Xi'an spy organization to secretly execute Xuan Xiafu, a senior senator of the 18th Group Army and a member of the Communist Party of China. This move triggered strong protests from the Communist Party of China. Under pressure from public opinion, the Kuomintang was forced to set up a special agency for counter-revolution in Xi'an to investigate the disappearance of Xuan Xiafu. Wu Zhongming, an underground member of the Communist Party of China and a former agent of the Central Bureau of Investigation, became a counter-revolutionary commissioner recognized by both the Kuomintang and the Communist Party. The special agency for counter-revolution, led by Wu Zhongming, brought together various forces from the Xi'an Army, police, special forces and the Xi'an Office of the Eighth Route Army. There were enemies among us and enemies among us. The intricate and complicated investigation journey was full of traps and crises as soon as it started! Wu Zhongming thoroughly investigated the Xuan Xiafu case for two months. It was not only a duel on the blade, but also a contest of human nature. Under the leadership of the underground party organization and the pursuit of justice comrades, Wu Zhongming finally found out the truth and got the handwritten order to secretly execute Xuan Xiafu. Under the pressure of irrefutable evidence, Chiang Kai-shek had to admit his guilt to the Communist Party of China and suffer the consequences!