Ex-cop pimp Joong-ho is irritated because his girls keep disappearing without clearing their debts. One night, he gets a call from a customer and sends Min-ji. Joong-ho realizes the phone number of the customer matches that of the calls the missing girls got last. As something smells fishy, he searches for her. During his search, Joong-ho dents a car in the alley. When he spots blood splattered on the driver's shirt, he senses the man, Yeong-min, is the suspect. After an intense chase he catches Yeong-min. But because of Joong-ho's pretense as a cop, they are both taken to the police station. At the station, the man bluntly confesses he has killed the missing women, and the last girl, Min-ji, may still be alive. As the whole police force is obsessed with a random search for corpses, Joong-ho is the only one who believes Min-ji is still alive. With only 12 hours left to detain the serial killer without a warrant, his hunt begins, searching for Min-ji trapped in a place nobody knows.