A serial killer ruthlessly hunts down a deaf woman through the streets of South Korea after she witnesses his brutal crime.

Chief of the ‘Special Crime Unit’, OH Gu-tak, looks for the former gangster, PARK Woong-chul, whom he had worked with before, and recruits a con artist, KWAK No-soon, and a convicted cop, KO Yoo-sung in the new team. With new blood, the ‘Bad Guys’ have become stronger and tougher. As they dig deeper into the case, they sense that a much bigger crime organization is behind it all and they begin the hunt for bad guys…