A shy and meek young boy named Yugi Mutou is a student at Domino City High School, who is bullied by his classmate Katsuya Jonouchi. The hall monitor, Tetsu Ushio, forcibly becomes Yugi's bodyguard, beating up Jonouchi and Hiroto Honda, and then says that Yugi owes him money. Ushio later beats up Yugi for failing to pay up, but Jonouchi and Honda try to intervene, only to be beaten up as well. One day, Yugi solves the Millennium Puzzle after working on it for eight years, heralding the return of the Shadow Games. In the process, he unknowingly changes his own life forever by releasing a dark alter-ego named "Yami Yugi", who challenges Ushio to a Shadow Game...