Operating a pawn shop in a small neighborhood, Cha Tae-sik now leads a quiet life. His only connection to the rest of the world is a little girl, So-mee, who lives nearby. A heroin addict and So-mi’s mother, Hyo-jeong, smuggles drugs from a drug trafficking organization and entrusts Tae-sik with the product without his knowledge. When the traffickers find out about this they kidnap both Hyo-jeong and So-mi. The gang sends a number of thugs to Tae-sik’s pawn shop to retrieve the stolen drugs, but is easily overpowered by Tae-sik, making his identity ambiguous. However, upon learning that the gang now has in their possession both Hyo-jeong and So-mi, Tae-sik gives the beaten gang members what they are looking for.
Realizing that Tae-sik may serve better as a mule than their former thug, the brothers that lead the gang — Man-sik and Jong-sik — promise to release Hyo-jeong and So-mi under the condition that Tae-sik make a delivery for them. Tae-sik makes the decision to face the outside world in order to rescue So-mi. However, the delivery was part of a larger plot to eliminate a drug ring superior, Mr. Oh, and Tae-sik is arrested. At the same time, Hyo-jeong’s body, with her organs harvested, is discovered in the back of the car used by Tae-sik when he made the delivery, and Tae-sik realizes that So-mi’s life may also be in danger. He fights off half a dozen detectives and escapes from the police station. During his escape, the police are bewildered at Tae-sik’s display of power, combat techniques and agility, and further investigates his bio and finds out that he was once a black operation agent for the Korean government with numerous commendations, but dropped out from the agency after witnessing his pregnant wife being murdered in front of his eyes in connection with him by being hit by a truck while inside their car. The incident nearly drove him mad, hence he went into hiding.
Realizing this, the Narcotics head contacted a weakened Tae-sik after his encounter with a highly trained assassin who backs up the brothers. Now with the knowledge that So-mee is being used by an ANT organization to secretly smuggle drugs and – in the future – might be killed for organ harvesting, Tae-sik goes on a mad killing.hunting spree to locate and save So-mee, who is his only connection to a caring world.