Five years ago UGan was killed by an organization involved in drug trafficking under the alias "K", and his son U Zhengfeng was expelled from the police. U Zhengfeng got on a bus to the border, while his best friend Chen Yu tried to catch up with him. On the way, saving his friend, U Zhengfeng was kidnapped by drug traffickers. When they meet again, Chen Yu works as a police officer in the anti-narcotics department, and U Zhengfeng is a murder suspect. Despite public opinion, Chen Yu decides to uncover the truth and clear his friend's name.