After the allied Mecha Human Professor Shibata is abducted by Gear, Bioman searches for him until Peebo tracks them to Neograd using the abducted mecha Balzion. They are closely followed by the Anti-Bio android Bio Hunter Silva, who uses them and his tracking of Bio Particles to likewise reach Neograd and retake Balzion for his own. Shuichi Kageyama, the son of Doctor Man during his previous life, likewise sneaks in using the guise of the leader's former android "son" Prince (attempted to be used by Silva as a bargaining chip) in hopes of trying to have a final chance to save his father. Bioman become trapped within one of the prisons before Shibata sacrifices his life for their escape; then face Silva in the Antarctic wasteland around the fortress in their final battle between Balzion and