In 1940, multiple forces occupied Nanjing. Agent Jin Shenshui (played by Zhang Yi) spent his days dealing with the Japanese military, the Wang Puppet Government and the Military Control Commission. He was like walking on the edge of a knife. With multiple identities, he lived cautiously in the devastated city of Nanjing, hiding his true self and looking for a way out for himself and the entire nation. Until he met Lin Yingying (played by Lang Yueting), who had the same hatred for the country and family as him but seemed to be more at ease than him, in the process of fighting side by side with her and fighting openly and secretly against various forces, Jin Shenshui, who was trying to survive in the troubled times, began to truly awaken for the first time...