Nagi is a diver from a quiet fishing village where a series of strange incidents have been occurring recently, including residents that have gone missing. One day, a stranger takes her to an office where she is asked to recover sunken treasure at Kaijin Reef. Nagi agrees to do so, but during her dive, she gets exposed to strange radiation. Afterwards, she starts to experience moments where she exponentially grows in size. This causes a lot of problems for her and the people surrounding her.

The Kyowakai, aiming for nationwide domination from Kansai. The Kurosaki-gumi, led by Asakawa (Kazuyoshi Ozawa), contributed greatly to their expansion into Kanto, but he became the target of relentless harassment from Wakagashira Kito. Unable to endure it any longer, Asakawa slashed Kito and was expelled, only to be assassinated soon after by an unknown hand. It is then that Sejima (Hakuryu), the Kurosaki-gumi’s Wakagashira, returns after serving his prison sentence. With the quiet flames of vengeance burning within him, he sets out on a path of retribution.