Vita is a rookie genius in psychological research. Her brain works as if there were a rapid generator in it. In fact, it is a gifted talent as a snail. Upon joining the police force, she is facing the fate of getting removed due to her weak physique. Since Officer Pla is the only one that can help her, Vita tries everything to make Pla take her in as his mentee. As the captain of the Police Investigators Team (PTI), Pla is one of the few brilliant, experienced, and skilled investigators. At first, Pla does not take a liking to Vita. Besides, both are not on the same page regarding how to deal with cases. However, having joined hands and solved a series of cases, Pla begins to fancy this innocent yet witty mentee of his. Alas, Vita, who is as dull as a snail, does not feel Pla's love. When the two of them are talking about love and cases, the spooky serial killer is back. Pla and Vita finally acknowledge their feelings toward one another in the face of danger. Pla has always been bothered by the Luger case, which has reopened. The lovers are once again joining hands to embark on an extremely menacing journey of catching the criminal....