Aku, an evil shape-shifting demon, devastates a boy Japanese prince’s land and abducts his father. After years of training in exile around the world, the prince returns as a young man, receives a samurai outfit and a mystical katana, frees his people from Aku’s minions, and battles Aku despite his father’s warnings. Before the prince can strike the killing blow, Aku opens a time portal to send him into the future.