The Mikumo family, known as the "L family" and whose family business is thievery, had deceived the public into believing they were all dead and were staying at the home of Hana's (Kyoko Fukada) boyfriend, Kazuma Sakuraba (Koji Seto). However, the Sakuraba family were police officers. Meanwhile, in Kyoto, middle school student Hojo Mikumo (Hashimoto Kanna) was receiving detective training from her grandfather and head of the family, Soshin (Ibuki Goro), at the Hojo family home, a family of famous detectives.