In the past, Shizuri Maki (Kyoka Suzuki) worked as a detective. She was partners with Detective Maeda while working on a murder case involving a robber. During their investigation, Detective Maeda was injured while covering Shizuri Maki and died from his injuries. Shizuri Maki then quit her job. One day, Shizuri Maki meets Sakito Nakamoto (Koji Seto) in front of Detective Maeda's grave. Sakito Nakamoto is Detective Maeda's son.