Shanghai in 1938, the party decided to wake up senior special agent Lin Chufeng. In order to complete the task, the superior decided to send female operator cold plum wife name to assist Lin Chufeng work. Lin Chufeng and Mei Leng accident in the joint, Lin Chufeng think juntong agent clouds are cold plum, the clouds also mistakenly believed Lin Chufeng was assigned to her husband Liu Fulin, two people back home only to find each other's true identity. Because Lin Chufeng and the clouds are an important mission, in the Anti-Japanese joint is higher than all of the premise, the superior decided to joint intelligence group composed of Lin Chufeng and clouds in the name of husband and wife, code-named "shadow". At the same time, cold plum and Liu Fulin only to another couple identity lurking down, assisted Lin Chufeng with clouds work, both the ultimate sacrifice. During the execution of the task, Lin Chu Feng and clouds from faith to behavior are collided conflicts, but two people together, or completing a mission impossible. At the same time, the clouds are also deeply in love with Lin Chufeng, but such love is doomed to no results, can leave a regret.