Obsession is like a shadow

A series of stories triggered by the police duo Luo Song and Gao Chuan's pursuit of the accidental murder of their mentor Cheng Fenghua. After Cheng Fenghua's death, Gao Chuan left the police force for some reason, but he was still obsessed with investigating the truth about his mentor's death. The series of cases that happened one after another also made Luo Song more suspicious of Cheng Fenghua's murder. The two heroes join forces again, but little do they know that they have fallen into a life-and-death dilemma carefully planned by the mastermind behind the scenes.