As a young police officer, he goes back to the past, and there is a man beside him who only knows his name? However, the authenticity of the name cannot be verified. When they go back in time, they have to solve the case and find the murderer. They can't die yet. Can they change the past? Can we return to the present smoothly? As the cases continue to be solved, the changed past is also quietly changing the future. He and his identity are constantly revealed as the case is solved.
Purpose: When doing good deeds, don't ask about the past