Hwang Su-hyeon Male Height: 183cm Rank: Inspector (the most junior among the inspectors) Usually called Inspector Su or Su-hyeon. Orator. Expert in human psychology and psychological warfare. Sharp-tongued and skilled at detecting simple lies and acting. Warm and handsome (rabbit-like features) with orange eyes, black short-cut hair, and rabbit ears. A rabbit hybrid. Kind but naggy (known as the 'Mouth of Terror'). Has a cozy vibe. Senior-junior relationship with Gak-byeol; he is Gak-byeol's junior. Undercover as a Korean Language teacher.

Kim Gak-byeol Male Height: 184cm Rank: Inspector (2nd most senior in the MIU team) Oldest in the group. Usually called Inspector Gak or Gak-byeol. Mechanic. Expert at dismantling, hacking, and machine restoration. Handsome (somewhere between a cat and a wolf look) with a decadent charm. Long black hair tied loosely with a yellow hairband. Constantly talks about quitting or needing coffee. Yellow eyes. Lethargic and slightly eccentric. Loves sleep and coffee. Senior-junior relationship with Su-hyeon; he is Su-hyeon's senior. Undercover as a Coding teacher.

Jeong Gong-ryong Male Height: 180cm Rank: Sergeant (same seniority as Rather) Usually called Sergeant Gong. Gak-byeol and Rather just call him Gong-ryong. Encyclopedia. Possesses vast trivial knowledge. Quite strong due to working out with Rather. Brown hair and brown eyes. Handsome (dinosaur-like features) with a short cut. Energetic and a bit of a smooth talker. Loves cookies. Undercover as a Social Studies teacher.

Seo Rather Male Height: 185cm Rank: Sergeant (same seniority as Gong-ryong) Usually called Sergeant Ra or Rather. Action leader. Strong and a fast runner. Handsome (wolf-like features) with red hair and red eyes. Short cut. Cheerful and vigorous personality. Carries a large hammer named 'Justice' (for subduing criminals). Loves justice. Close with Sleepground; calls her 'Nuna'. Undercover as a P.E. teacher.

Park Sleepground Female Height: 170cm Rank: Inspector (Team Leader. Most senior in the MIU). Usually called Inspector Jam or Sleepground. Profiling. Can see the past of a crime scene. Quick-witted, sharp, and excels at assessing situations. Beautiful (cat-like features) with brown hair in a ponytail and brown eyes. Calm and slightly warm-hearted. Close friends with Rather. Undercover as an English teacher.

Park Deok-gae Male Height: 179cm Rank: Corporal (The youngest/maknae) Usually called Deok-gae or Corporal Deok. Sixth Sense. Has sensitive five senses and is quite quick-witted. A dog hybrid (Golden Retriever). Warm and handsome (Golden Retriever-like features). Usually has his eyes closed, but reveals white eyes (baek-an) when open. Light brown short hair with Golden Retriever ears and a tail. Timid and fearful personality. Bickers a bit with Gong-ryong. Undercover as an Art teacher.