An anonymous letter is delivered to the Tokyo Metropolitan Police Department. The letter states that a criminal of a murder case will appear at the countdown party Masquerade Night that will be held at Hotel Cortesia Tokyo. Detective Kosuke Nitta must go undercover and work again at the Hotel Cortesia Tokyo. There, he meets Naomi Yamagishi, who works as a concierge. Without any information about the criminal, except that the person will be in attendance, Detective Kosuke Nitta works feverishly to find the criminal among the 500 attendees.
木村拓哉
as Kosuke Nitta
長澤まさみ
as Naomi Yamagishi
小日向文世
as Kazuhiko Nose
木村佳乃
as Machiko Sono
麻生久美子
as Midori Nakane
沢村一樹
as Atsuya Kusakabe
石黒賢
as Yusaku Ujihara
中村アン
as Mayumi Okuda
高岡早紀
as Yuri Kaizuka
梶原善
as Masaharu Motomiya
勝村政信
as Masaaki Sono
博多華丸
as Mikio Urabe
