Many stories and rumors circulate in most regular high schools—some scandalous, some joyous, and others...more macabre. Monsters hiding in an abandoned home outside of town is one such example. Such stories, on the other hand, are too seductive for Hiroshi and his buddies Mika, Takeshi, and Takurou to ignore. They decide to investigate the estate and undergo a bravery test despite the alleged perils. Each of them is filled with fear as they approach the mansion. When they enter, they are attacked by a blue monster known as Ao Oni.