The story of the two police heroes Luo Song and Gao Chuan, who were investigating 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 of his mentor's death. The series of cases that occurred one after another also made Luo Song more suspicious of Cheng Fenghua's murder. The two heroes joined forces again, but they didn't know that they had fallen into a life and death mystery carefully planned by the mastermind behind the scenes.