Ayame is an unsuccessful girl celebrity, who happens to take on the PR role of a "police chief for a day". The job of a campaign girl is to smile and act as a police chief for one day. It should have been a simple job, however, the police station staff treat her like the real police chief and look to her for instructions, which makes Ayame feel perplexed. In addition, she runs into her ex-boyfriend, Haruki, who is now a detective at the station, which means her ex is her subordinate for the day. Furthermore, Haruki holds a dreadful secret which was the cause for the couple's separation. To make matters worse, a major event takes place on that particular day, and the situation takes an unexpected turn. Would Ayame be able to solve the case, and what is Haruki's secret?