Three kids' robots built for a school competition become real weapons overnight. Professor Mizuki doesn't ask permission, he just takes what they made and repurposes it for war. That collision between innocent creation and forced militarization is the actual story here, not the alien invasion playing in the background. You're watching teenagers process the moment their passion project becomes a tool, their ingenuity weaponized without consent. The mecha itself is secondary. The cost of being useful when the world needs soldiers is everything.
Three high school roboticists build cutting-edge machines for a school competition. Daisaku, Tetsuya, and Hotaru pour everything into their designs, creating robots that push the boundaries of what young engineers can achieve. Their moment of glory gets interrupted when an alien threat emerges. The Derinja, a hostile extraterrestrial race, sets their sights on conquering Earth as part of a larger galactic conquest. Hotaru's father, Professor Mizuki, recognizes the danger nobody else sees coming. He requisitions his daughter's robot and her friends' creations, retrofitting them with weapons and defensive capabilities the students never intended. What were competition prototypes become humanity's first line of defense against an otherworldly invasion. The three teenagers transform from ambitious young engineers into reluctant pilots of a combined super robot called Albegas. They navigate the weight of unexpected responsibility while learning that their technical skills matter more than ever before. Earth's survival depends on three students who just wanted to win a school prize.