In December 1949, the country's public security department intercepted a secret telegram from an enemy Taiwan, which involved a visit by the Chinese delegation to the Soviet Union. The public security department immediately informed the central government, which instructed the delegation to ensure the security of the delegation's visit at all costs. After receiving instructions from the central government, the Ministry of Public Security immediately launched an operation to clean up secret radio stations and capture lurking enemy agents. In order to ensure the safety of the special train for the CCP delegation, Qiao Changjun, a scout for the Ministry of Public Security, was ordered to run to Harbin, where the enemy was ambushed, and penetrated inside the enemy. After countless sleepless nights of life and death, Qiao Changjun took the opportunity, cooperated with Yang Weizhong both inside and outside, and finally eliminated the secret liaison station and the desperate task force in Heilin Villa, which had been operated by the "Godfather" for many years, ensuring the safety of the special train.