A young boy named Yugi Moto solves an Ancient Egyptian Puzzle and brings forth a dark and powerful alter ego. Whenever he and his friends are threatened by evil, this alter ego breaks out of the confines of the Millenium Puzzle and challenges wrongdoers to the Shadow Games: Life or Death situations that test the true nature of human beings. Those that lose or cheat suffer serious penalties that result in losing their sanity or even their lives. Along with his friends Joey, Tristan, Téa and Miho; Yugi and his dark counterpart faces off against foes such as Seto Kaiba: The ruthless champion of the duel monsters card game; and Ryo Bakura, who possesses the Millenium Ring containing a spirit more brutal than Yami Yugi. Will Yugi and his friends succeed or will they lose their souls?