In a technical high school, three gifted students - Daisaku, Tetsuya, and Hotaru - collaborate to craft prize-winning robots for a school contest. Meanwhile, the sinister Derinja clan, with dreams of universal domination, sets its sights on Earth. To thwart this peril, Professor Mizuki, Hotaru's father, adapts the trio's robots for warfare. Thus, Albegas, the mighty super robot, emerges.