"Even the most loyal of dogs will bite if you mistreat them." Yong Gae is a rowdy gangster from Musan with no home, no background and nothing to lose. He's the loyal dog of Chairman Choi, his boss, and does even the dirtiest task he asks. One day he meets Soo Yeon, the daughter of a debtor. Yong Gae, who used to think being born in and dying in Musan wasn't so bad, falls for Soo Yeon and decides to leave Musan for the first time. However, Chairman Choi orders for him to be killed, and Yong Gae is provoked by his rival, Sang Cheol...