Player 456 is the main protagonist of the Squid Game series, whose real name is Seong Gi-hun. Played by actor Lee Jung-jae, Gi-hun is an ordinary man, a divorced father and a worker with serious financial problems. After participating in a mysterious game to pay off his debts, Gi-hun finds himself involved in a series of deadly games where the participants, all in financial difficulty, are forced to fight for survival in exchange for a huge cash prize.

In the context of the game, Gi-hun is identified by the number 456, which represents his code during the various trials. Despite initial difficulties, Gi-hun proves to be a complex character, who grows throughout the series, developing courage, empathy and determination as he tries to survive and protect the other participants. His story is that of a man who, despite his flaws, strives to do the right thing in a brutal and inhuman context.