Ling Jing (played by Huang Xiaoming) has been the top sniper in the Hong Kong police force for four consecutive years, earning high praise from his superiors and teammates. However, he has a high opinion of himself and doesn't like to socialize much; his only happiness comes from the companionship of his wife. During a crackdown on criminals, Ling Jing accidentally kills a hostage—the son of the richest man in the city. The wealthy businessman puts constant pressure on the police department, and Ling Jing is ultimately sentenced to four years in prison for manslaughter. Since Ling Jing's departure, the former second-best officer Ke Ming (played by Ren Xianqi) has become the strongest one, having made false testimony that led to Ling Jing’s imprisonment. Ling Jing vows to take revenge on the police force that betrayed him and on Ke Ming. O Zi (played by Edison Chen) is a top student at the police academy with exceptional shooting skills, and he is soon recruited by Ke Ming to join the Hong Kong police sniper squad. After hearing about Ling Jing's story, he becomes curious and meets Ling Jing by chance, receiving guidance from him, and they become friends. Ling Jing frequently provokes the police force, prompting the entire sniper squad to mobilize to capture him. Ling Jing fights fiercely, taking on the police force alone. However, Ke Ming uses himself as bait with O Zi's assistance, causing Ling Jing to inadvertently reveal his location. In the end, which side will emerge victorious? And will Ling Jing find the justice he deserves?