1. Protagonist: Mao Genshun
- Identity: A 30-year-old hair salon owner in Changsha, running Genshun Hair Studio. A technically minded hairstylist who fancies himself “the modern-day Di Renjie,” he has an almost obsessive knack for logic.
- Personality: Hilariously sharp-tongued. He likes cracking dirty jokes to entertain his customers, but takes every case more seriously than anyone else. His deductions are terrifyingly precise: he can infer a killer's height and weight from a single broken hair.
2. Supporting character: Niu Dazhuang
- Identity: Mao Genshun's roommate. A former weightlifter, he has incredible strength but little brains, serving as both the muscle and the comic relief.
3. Main antagonist: Zhaocai, a cat
- Identity: A stray cat Mao Genshun brought home from a trip to Fenghuang Ancient Town. Its fur is golden all over, and it wears a battered copper coin around its neck.
- Traits: It looks adorably silly, but is actually a “high-IQ criminal” behind a string of crimes.
