Assistant Inspector Sugiyama Shintaro is a compassionate detective who works for Kichijoji Police Precinct. The cases he has solved are too many to count. Once he comes back home, he is a father to the three children, Miharu, Kaito (Suda Eito) and Gaku (Matsuura Rihito), he has with his beloved wife Kaori. However, he cannot deny that he has sacrificed his family because he has been busy at work. At that very moment, Kaori is fighting against an illness in hospital and his mother-in-law (Takahashi Keiko) is not pleased with him. Sugiyama has focused on the family ever since his wife fell sick. He has even considered a move away from the frontline and Kichijoji Police Precinct’s arrest rate has consequently declined. Then, a murder occurs within the precinct’s jurisdiction. Sugiyama strives to juggle child raising, housework and the investigation. However, he can hardly do so as he ends up late for a meeting because he has to send his children to nursery school. Unable to just watch without doing anything, his mother-in-law declares that she will take custody of the children. Sugiyama makes the decision to quit being a detective, but…