Yuzuru Hamura (Ryunosuke Kamiki) is a university student and a fan of mystery novels. Against his will, he was forced to join the school's mystery club. The club is led by Kyosuke Akechi (Tomoya Nakamura). Meanwhile, Hiruko Kenzaki (Minami Hamabe) appears in front of them. She attends the same university and she is also a private detective. These 3 people attend a summer camp and stay at Shijinso pension in the mountains. On their first day there, they must barricade themselves in the pension. The next morning, they discover a murder has taken place in the pension.
as Yuzuru Hamura
as Hiruko Kenzaki
as Haruya Tatsunami
as Kanemitsu Nanamiya
as Reika Hoshikawa
as Rin Takagi
as Ayumu Shindo
as Yuito Kanno
as Kyosuke Akechi
as Sumie Nabari
as Tobio Deme
as Kirei Mifuyu Shigehara
as Mitsuru Shigemoto