A wild sukeban of coast side Chiba, Hirata Taiko is attacked by an underwater speargun. Incidentally, Saki and Okyo are visiting Yukino, who is hospitalized around this area, and are taken as the attackers just because they are the strange sukebans from outside. Okyo is taken as a hostage and Saki has to arrest the real attacker in order to free Okyo.
Saki finds out that one of Taiko's subordinates is controlled by Seirokai and she attacks her. Seirokai has a plan to build a training center on this coast and feeling resentful toward Taiko, who would not sell the space for that.
Taiko teams up with Saki and defeats Seirokai's surfer army. Okyo is saved and she and Saki leave for Tokyo with Yukino, who is freed from the hospital. Saki meets Taiko again and they promise to beat Seirokai together.
