Daisuke Yamamoto was raised in the Amazon after his parents were killed in a plane crash. His life is changed when the Ten-Faced Demon attacked and destroyed his adopted home village. A witch doctor inserts the mystical Gigi Bracelet into him, which allows him to transform into the warrior Amazon. He goes to Japan to meet a professor who knew his father, battles Gorgos's minions after the professor is killed, and becomes the new Champion of Justice.