The Oni, a horde of demonic beings, are launching an assault on humanity. With conventional warfare proving ineffective, Dr. Saotome, a brilliant scientist, develops an arsenal of colossal robots infused with Getter Rays, a formidable energy source, to counter the Oni. The mightiest of these machines is the Getter Robo. In order to operate it, Saotome must recruit three contrasting personalities - Ryoma Nagare, a skilled martial artist, Hayato Jin, a notorious criminal, and Benkei Musashibou, a respected monk. Together, the trio forms the Getter Team and engages in a final showdown with the Oni to put an end to their evil for all time.