Kang Sae-byeok

Kang Sae-byeok, Player 067, is a North Korean defector who enters the Squid Game to earn enough money to rescue her mother still trapped in the North and to provide a stable life for her younger brother Cheol living in a South Korean orphanage. Her stoic, guarded exterior masks a fierce determination and a well of suppressed emotion.

Sae-byeok is a survivor long before she enters the games. Having escaped North Korea, navigated the dangerous underground defection route through China, and scraped by in South Korea's margins, she approaches the games with a streetwise pragmatism that serves her well. She is initially a lone wolf, trusting no one and picking pockets to survive, but gradually allows herself to connect with Gi-hun and his group.

Her most vulnerable moment comes during the marble game when she is paired with Ji-yeong, a fellow young woman who has nothing to live for. Ji-yeong deliberately loses so that Sae-byeok can survive, giving her life as an act of pure selflessness. This sacrifice cracks open Sae-byeok's emotional armor and represents one of the show's most powerful commentaries on human connection amid dehumanizing conditions.

Sae-byeok's death at the hands of Sang-woo — who slits her throat while she lies wounded from the glass bridge game — is among the series' most devastating moments. She never gets to see her brother again, and her story becomes the driving force behind Gi-hun's determination to care for Cheol and ultimately return to destroy the games.