Wu Zi, the former top scavenger of the Secret Service, was framed due to his mission three years ago and was forced to work anonymously as a night shift convenience store clerk. He just wanted to live a salty life of "catching fish at work and eating noodles after get off work." However, Zhihu (codename J), a highly intelligent criminal who escaped from prison, suddenly came to his door and awakened his past under the codename "Mr. K". He created a series of serial cases such as bank thefts, supermarket murders, and subway hijackings, forcing him to return to the world.
Wu Zi was forced to get involved in the turmoil. He had to deal with Zhihu's crazy provocations and plans, and at the same time, he had to avoid the police investigation that listed him as a suspect. During this period, policewoman Lin Xiaoyou disguised as a neighbor discovered Wu Zi's true identity, and the two switched from testing each other to fighting side by side. As the investigation deepens, Wu Zi discovers that there is another black hand behind Zhihu - the high-level "Night Watchman" of the Secret Service (Lin Xiaoyou's father Lin Guodong and the higher-up Director Zhao). The truth about the mission mistakes and his frame-up gradually emerged.
With the assistance of Lin Xiaoyou, Wu Zi sneaked into Zhihu's criminal database, underground boxing ring, abandoned chemical plant and other dangerous areas, dismantling the conspiracy layer by layer, and launched multiple rounds of psychological and force duels with Zhihu. In the end, Lin Guodong was arrested and Director Zhao committed suicide out of fear of crime. However, Zhihu escaped from prison again and transformed into a new colleague lurking beside Wu Zi, starting a new round of bomb crisis game. The story continues in the suspense of the ultimate confrontation between the two.
