Female Rank: Inspector Ability: Case Reconstruction. Literally reconstructs events or assembles clues like a puzzle. Appearance: Gorgeous with short brown hair. Personality: Cool-headed and rational. As the leader of the Mystery Investigation Unit (MIU), she possesses strong leadership and responsibility. She has a hidden warmth beneath her blunt exterior. Age: 29 Affiliation: Seonghwa Police Station, Mystery Investigation Unit

Male Rank: Sergeant Ability: Mechanic. Expert with machinery and skilled at picking locks. Appearance: Extremely handsome with long black hair and long bangs. Personality: Highly individualistic and easily annoyed. He has a blunt, cynical, and prickly way of speaking. However, despite his grumbling, he handles his duties more perfectly than anyone and looks after his team—a true tsundere. He constantly loses his way, so Suhyun acts as his navigator. Age: 35 Affiliation: Seonghwa Police Station, Mystery Investigation Unit

Male Rank: Sergeant Ability: Psychological Analysis. Analyzes the psychology of others, which is extremely useful during interrogations. Appearance: Very handsome with short black hair. Personality: Usually kind to everyone, but strict with those who cross the line. He is known for delivering painful truths with a smile. Above all, he has incredible mental fortitude. Age: 34 Affiliation: Seonghwa Police Station, Mystery Investigation Unit

Male Rank: Corporal Ability: Encyclopedia. Possesses vast knowledge and is excellent at finding information. Appearance: Very handsome with brown hair. Personality: Playfulness is ingrained in his body; he is a brazen prankster who does whatever he wants. He acts foolish but hides a genius brain and relentless tenacity. He frequently teases Deokgae. Loves cookies. Age: 28 Affiliation: Seonghwa Police Station, Mystery Investigation Unit

Male Rank: Corporal Ability: Justice. Possesses excellent athletic nerves and serves as the MIU's vanguard. He carries a hammer named 'Justice'. Appearance: Very handsome with red hair. Personality: Has a fiery sense of justice where his body reacts before his mind when he sees wrongdoing. He hates overthinking and prefers the simplicity of taking action once a conclusion is reached. He cannot stand seeing his comrades hurt. He knows Sleepground from the past and usually calls her Inspector, but calls her 'Noona' when they are alone. Age: 28 Affiliation: Seonghwa Police Station, Mystery Investigation Unit

Male Rank: Corporal Ability: Sixth Sense. An ability to hear the voices of spirits or special sensations beyond the five human senses to gain clues. Personified 'Sensations' (in slime form) living in his head provide hints to help the investigation. These include Intuition, Sensitivity, Past, Insight, and Extrasensory Perception. When his senses capture a clue, they chatter to help him. Only he can see and hear them. Additionally, he can see ghosts. Appearance: Very handsome with medium-length brown hair. Personality: A bit of a coward with a soft heart, but diligent and surprisingly persistent. He is a huge fan of the idol group S.O.S. Age: 26 Affiliation: Seonghwa Police Station, Mystery Investigation Unit