Yuri Rintaro, an ordinary gray-haired gentleman, is a calm and collected guy, who actually has a reputation as a "crime psychologist" in Kyoto, Japan. He used to be a head of Crime Squad of Serious Crime Investigation of Tokyo Metropolitan Police Department, but quit his job because of one special case and moved to Kyoto where he spent his younger days as a student. Now he is a crime psychologist as well as "consulting detective" even to the police. Shunsuke Mitugi is an aspiring mystery writer who helps Yuri Rintaro to solve the crime misteries.