This anime follows a guy named Nagate Tanikaze as he fights giant alien monsters in space. He was recently enrolled in a school that trains students how to pilot giant robots if giant alien monsters ever invade their ship. Their help is crucial because the ship contains some of the few surviving humans in the entire universe after the alien monsters successfully wiped out the solar system. It’s been a hundred years since the last contact with the aliens though so all is good so far. Nagate lived underground all his life so there are some people ready to ridicule and belittle him. He isn’t that affected but adjusting to life above ground is certainly proving to be challenging. To make matters worse, the first sight of an alien monster has been confirmed after years of silence and now a bunch of inexperienced pilots like Nagate is soon thrown to the wolves. For the survival of mankind, they fight but humans being cornered often brings out the ugliness in all of us.