In the year 2045, top scientist Hiroshi Ozora invents the Mol Unit, a costume that gives its user superhuman abilities. He uses the Unit to become the hero Captain Tokyo, and earns himself fame and glory... then his younger sister Mirai comes across the suit. A simple ordinary girl interested in shopping and beauty products, she accidentally alters it to fit a feminine user. Now with the Mol Unit switching between a male and female costume, Hiroshi is forced to introduce Mirai to the world, as the new superheroine Moldiver! All Mirai wants to do is play around in the suit, but when things start to escalate with the arrival of the evil Dr Machinegal and his female android army, Mirai must step up to take on this threat.