Wang Wei Ye (played by Daniel Wu), a police officer for seventeen years, is extremely anxious due to childhood and family issues, yet he maintains an absolute sense of justice, which causes him to be overly stringent in his interactions, leading to difficulties in communication with colleagues. One night while stationed in the emergency room, Wei Ye gives a blood transfusion to a critically injured patient with a rare blood type, only to find out that the patient is Han Jiang (played by Zhang Jiahui), the leader of a notorious bank robbery gang. As a result, Wei Ye faces condemnation from his colleagues, and soon after, Han Jiang manages to slip away and leads his gang to commit heinous crimes, resulting in the death of Wei Ye's colleague in a shootout. What one does, heaven sees; the violent and domineering Han Jiang never anticipated that he would be ruthlessly consumed by his own desires. Meanwhile, Wei Ye's mental state becomes increasingly concerning as he refuses psychological counseling and obsessively tracks down Han Jiang's associates like a specter. He witnesses betrayal and slaughter while watching the collapse of his strong inner beliefs...