Jinpei has left to bring a detector to a secret ISO research institute in the Rakki mountain chain. When he is almost there, an earthquake hits. Jinpei sees a young orphaned puma and does not bring the detector to the institute. However, that institute is destroyed by the unusual earthquake. After Jinpei returns, he gets rebuked by Joe and Ken because he took care of the puma. Then it becomes known that there was poisonous Sarin gas in the research institute which now threatens to leak out. Joe and Ryu go to investigate, while Ken and the others are supposed to follow with a neutralizer. But another earthquake occurs and the two men are imprisoned below the research institute. Jinpei has heard the news, and leaving Ken and the others, goes alone again to the Rakki mountain chain. Not relenting, he returns the puma to nature. Jinpei arrives at the ruins of the research institute, kicks out Galactor who wanted to build a base there, and then continues to save Joe and Ryu. On their way out of the institute though, the Horned Tank Jinpei uses turns over, and Sarin gas enters. Gel Sadra escapes and laughs at their accident. But the God Phoenix arrives, and the poisonous gas which has started to leak out is rendered harmless by the neutralizer brought by the Phoenix. When Jun tells Jinpei "Well done", he answers "Jun...". Hasn't Jinpei always said "older sister"? Joe also notices that Jinpei has grown up.