Chang Zheng, the vice captain of the criminal police brigade, is investigating a shooting case in a suburban villa and locks up the suspect Zhao Pengxiang. The second child of the Zhao family, an inspector who didn't want to be involved in the death of Zhao Pengcheng, then becomes a wanted criminal. With the help of a secret investigation team dispatched by the Ministry of Public Security to investigate the truth, Chang Zheng not only faces confrontation with his relatives and loved ones, but also discovers his real identity. In the end, he discards his affection and chooses justice, and cooperates with the secret investigation team of the Ministry of Public Security to arrest the criminal.

1941年冬，我党地下党员李木胜在杭州暴露牺牲。牺牲前，李木胜将数十张鉴别日军“沉睡计划”位置的胶卷委托给学徒照相师陈开来，希望他前往上海交给我党。陈开来和落难舞女金宝结伴前往上海，意外卷入了“汪伪督查大员”苏门与76号头子内斗的漩涡中，经过贪墨案、跑马场刺杀案一系列案件，陈开来终于和代号“苏堤”的地下党员沈克希接头，交出了情报。我党也由此发现了陈开来过人的洞察能力，希望陈开来帮助分析照片线索，帮助粉碎敌人的“沉睡计划”。面对76号、日军、军统等几方势力，在地下党员苏门、赵前、沈克希竭力相助下，陈开来度过了重重危机，完成蜕变，彻底“醒来”，最终粉碎了敌人罪恶的“沉睡计划”，成长为一名真正的共产主义战士。

On the day of the 1949 Founding Ceremony, Xiao Dali (Lei Jiayin), who has just entered the city to be reorganized as the head of the public security police station, discovers that Feng Jingbo (Hu Ge), an elementary school teacher, is suspected of being suspicious. With the high alertness of a soldier and the sense of responsibility of a public security warrior, he is hard-partnered with Feng Jingbo as a neighbor, exhausting his life through trials and tribulations, and carrying out a nearly four-decade tracking without complaint or regret. The movie is based on Zhang Ce's novel.