Li Shan (Lee Min Ho) and A Yo (Wallace Chung) were once Interpol officers, but were dismissed from their posts due to mission failure and became private bodyguards. In a seemingly ordinary bombing case, the two met a bounty trio consisting of Ling Xin (Tiffany Tang), Swan (Karena Ng) and Bao Bao (Love Fan). After a conflict, they formed a bounty group that specializes in arresting criminals and maintaining social peace. After a series of thrilling missions, the five people successfully thwarted the serial terrorist attacks with their own unique skills and caught the black hand behind the scenes.