- **Mysterious Murder**: A serial murder occurred in Binhai City. The victims were all young women. They were injected with an overdose of insulin and died. The scene was carefully arranged in a confessional posture. The murderer left a "seven sins" note provoking the police.
- **Genius Profiler**: Criminal psychology expert Ke Wenrui was urgently recalled to help solve the case. He stayed away from the police force due to past trauma, but was persuaded by his old partner Cheng Feng to come back.
