A shy and meek young boy named Yugi Mutou is a student, 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, 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 an alter-ego, who is the «King of Games», and challenges Ushio to a Shadow Game. Ushio loses after a failed attempt to cheat, and Yugi enforces a Penalty Game upon him, which results in Ushio hallucinating that there were monsters coming out of a body of water that were about to eat him. After all of that, Yugi, Honda, and Jonouchi become life-long friends, with Yugi's childhood friend, Anzu Mazaki, and Honda's crush, Miho Nosaka, joining the group.