Fifty years in the future, after a terrifying alien species attacked our planet, teenager Stanford Yu works as a janitor at the Sky Corps Military Academy. But he's only dreamed of one thing his entire life — to pilot a Robo Mech, giant robots from outer-space who came to our aid. When he finally gets his shot, Stanford and his classmates must put aside all personal differences and work together as a team in order to defend humanity against a new invasion of aliens.