The Unknown Vigilante follows Lin Seo-jun, a 28-year-old detective assigned to capture a mysterious serial killer who is eliminating criminals with impunity on the streets of Seoul. The killer, Min Ji-hoon, is a brilliant 31-year-old surgeon who leads a double life, executing his victims with surgical precision. As Seo-jun dives deeper into the investigation, he finds himself caught in a dangerous game of cat-and-mouse with Ji-hoon. As he uncovers the corruption that allowed these criminals to escape justice, Seo-jun begins to question the system he was sworn to uphold. Caught between his duty as a police officer and a growing disillusionment with the justice system, Seo-jun must navigate a complex moral dilemma as he pursues the most clever criminal he has ever faced, in a city divided between those who see the killer as a hero and those who consider him a threat.
