In Iraq, a team of archaeologists uncovers ancient artifacts that foretell the arrival of a superior race and the collapse of all civilization. Meanwhile, in Graviton City, the rivalry between A-Ko and B-Ko over Kei escalates as Mr. Daitokuji arranges a marriage between Miss Ayumi and Kei. Enraged by the engagement, both A-Ko and B-Ko stop at nothing to thwart the wedding. Unbeknownst to them, another alien fleet is en route to Earth.