Haisheng (played by Nick Cheung), who has been an undercover agent for eight years, successfully arrested the criminal Dark (played by Francis Ng). Thinking that he can finally get rid of the undercover life, Haisheng feels that his life has returned to a bright future. However, things are not as good as Haisheng thought. The award ceremony for reinstatement was hastily done, and his colleagues did not show concern and appreciation for him, but looked at him with distrust. Police officer A Long (played by Anthony Wong) just comforted him silently. His girlfriend during the undercover period broke up with him, and strangers began to follow him. Haisheng felt that his life as a police officer was much more painful than undercover. He recalled the past between Dark and him when he was undercover, and he couldn't help but be moved. At this time, Haisheng's friend when he was undercover found Haisheng, and it turned out that escaping from the undercover career was far from that simple.