A team of archaeologists in Iraq uncover ancient artifacts that predict the arrival of a dominant race and the destruction of civilization. As A-Ko and B-Ko's competition for Kei's attention heats up in Graviton City, Mr. Daitokuji orchestrates a marriage between Kei and Miss Ayumi. Outraged by the proposal, A-Ko and B-Ko do everything in their power to halt the wedding. Unbeknownst to them, another squadron of extraterrestrial ships is en route to Earth.