The interrogation room loses power for three minutes. When the lights come back on, the witness has been replaced by someone else. The fingerprints and identity match perfectly, but the color of the person's eyes is different. Su Wantang, head of the Major Crimes Unit, quickly senses something is wrong, but meets layer upon layer of resistance as she investigates. Lu Zhaoming, a criminal psychology consultant, offers to help, yet seems to know more than he lets on. When Su Wantang discovers that the switch is part of a criminal enterprise whose trail leads straight to the unsolved case from three years ago, she must work alongside Lu Zhaoming, balancing trust and suspicion as they uncover the buried truth. Forensic pathologist Lin Xiaoman's findings, squad chief Chen Guodong's obstruction, and deputy director Zhao Haifeng's pressure make the case increasingly baffling. Then the mysterious operative Sun Qiaoyun appears, and Su Wantang realizes she is facing more than a case of mistaken identity: this is a war over memory and identity.
