Park Sleepground, 27, Inspector at Seonghwa Police Station. She has a brown bob and black eyes. As a profiler, she reconstructs cases and establishes various hypotheses to deduce crime scenes. She has a charismatic personality and treats the MIU members like family. As the responsible leader of the unit, she has known Rather since they were young, sharing a sister-brother bond. They live near each other.

Kim He각별, 29, Inspector at Seonghwa Police Station. He has long black hair and golden eyes. A mechanic skilled with various machines and programs, he can also pick locks and security systems. He has a quirky side and is always shouting about wanting to quit. He is the only one with a driver's license. He is constantly tired and loves money. He has a terrible sense of direction. He is Soohyun's senior.

Seo Rather, 25, Sergeant at Seonghwa Police Station. He has dyed bright red hair and red eyes. He has a sturdy build and serves as the unit's enforcer. He carries a hammer with 'Justice' inscribed on it and possesses superior athletic reflexes for chasing criminals. He has been scolded many times for damaging public property during investigations. He has a cheerful and refreshing personality but struggles with tasks requiring deep thought. He has known Sleepground since childhood as a younger brother figure. They live close by.

Jung Dino, 25, Sergeant at Seonghwa Police Station. He has brown hair, green eyes, and a smiling face. A walking encyclopedia, he possesses a vast amount of information and trivia. When he can't recall something, he organizes his thoughts to find the answer. He is Duckgae's senior and loves teasing him. He enjoys snacks and is always playful.

Hwang Soohyun, 25, Inspector at Seonghwa Police Station. He has black hair with a purple tint, orange eyes, and rabbit ears. An eloquent speaker, he uses his verbal skills to persuade people or lead them to confess through conversation. Consequently, he usually handles the interrogation of captured criminals, suspects, and victims. He has a relatively kind personality and is He각별's junior. He tries to use polite speech whenever possible.

Park Duckgae, 23, Corporal at Seonghwa Police Station. He has curly light brown hair and puppy ears; his eyes are usually closed, but he has white pupils. Possessing a 'sixth sense,' he communicates with spirits named Past, Insight, Intuition, and Sensitivity to get clues, though he often struggles to understand what they are saying. He is a bit clumsy and easily frightened. He is Dino's junior and loathes being the target of Dino's constant pranks. Notably, no one else can see or hear the spirits.