Yeong Jun, a Police Academy graduate, is a lieutenant working for the Internal Investigation Bureau; he is intelligent but very heartless as well. Now he's given the most fateful mission ever; to join an investigation team whose chief is Min Ho, his estranged father whom Yeong Jun hates more than anyone on earth. Min Ho is a completely different policeman, full of sentiment, and hunches. No doubt, they don't hit it off at all. They try to come up with a way to round up the gang as well as get over a long standing hatred and misunderstanding as well.