Ku Dong's life is going nowhere, spending his days beating people in the streets, he seems to be confined to repeat the same mistakes of his father, who happens to be already in jail. Even his younger brother is not far from going into the same tracks. Then a struck of luck, if you could call it that, hits Ku Dong, a crime syndicate kidnaps him in order to train him to pass the police admission exam. It's something they have been doing for a while, sneaking moles in the police force to protect their leader, and making it easier to do dirty jobs here and there. The training of Ku Dong is both painful and hilarious, a very black humour that seems to be something natural for Korean cinema The thing is, Ku Dong really wanted to be in the force, at first just as an excuse to keep beating people, but eventually starts to realize this is his chance to give his life a real purpose.