Vita is a budding genius in psychological research. Her brain works as if there were a high-speed generator inside it. In fact, she has the talent of a snail. When she joins the police force, she risks being eliminated because of her frail physique. Since Officer Prach is the only one who can help her, Vita does everything she can to get Prach to take her on as his protégé. As captain of the police investigative team (PTI), Prach is one of the few brilliant, experienced, and competent investigators. At first, Prach isn’t very fond of Vita. Furthermore, the two disagree on how to handle cases. However, after joining forces and solving a series of cases, Prach begins to appreciate his innocent yet witty protégé. Unfortunately, Vita—who is as slow as a snail—doesn’t reciprocate Prach’s affection. Just as the two are talking about love and cases, the menacing serial killer strikes again. Faced with danger, Prach and Vita finally acknowledge their feelings for one another. Prach has always been troubled by the Luger case, which has been reopened. The lovers team up once again to embark on an extremely perilous journey to capture the criminal.