Lin Zhen, a cutting-edge forensic doctor, first entered the police station. In a vicious poisoning case, he met Xiang Qing, a calm and sharp criminology expert. One is a technical genius who is obsessed with speaking out for the dead, and the other is a senior professor who has seen through the darkness of human nature. From the initial cautious cooperation, they later worked together to solve a series of bizarre murder cases - city-wide poisoning cases, thallium poisoning in colleges and universities, and the unknown female body in the sand field... They peeled off the cocoons at the crime scene and used science to restore the truth.
When the evidence was tampered with and the real murderer was covered up, the two repeatedly ran into obstacles in their pursuit of justice.
As the investigation deepens, they find that all clues point to a mysterious organization. In the process of searching for the truth, the two lonely souls gradually get closer and become each other's light in the darkness.
