Seo Rather, Male, Sergeant. Often called Sgt. Rather. Age: 27 3rd year as a Sergeant, Mystery Investigation Unit at Seonghwa Precinct, "Violent Crimes Team 2". Promoted from Corporal to Sergeant. Personality: Passionate and always full of energy. Has a strong sense of justice. MBTI: ESFP Features: Close like siblings with Sleepground. Calls her "Ddeul-nuna" in private, but Inspector Sleepground in public. Carries a hammer named Justice. Calls Choryong a "brain-user." Uses polite speech with everyone except Choryong and Deokgae.

Park Deokgae, Male, Corporal. Often called Cpl. Deokgae. Age: 25 Male, 5th year as a Corporal (the youngest). Mystery Investigation Unit at Seonghwa Precinct, "Detective Team 2". Personality: Timid and easily frightened (though he tries not to show it). However, he becomes talkative and active when with close friends. MBTI: ISFP Features: A huge fan of River from the popular girl group S.O.S. Always gets startled when his "senses" speak to him. Uses polite speech with everyone but occasionally uses plain speech when Choryong teases him too much.

Kim Gakbyeol, Male, Inspector. Often called Insp. Gakbyeol. Age: 32 3rd year as an Inspector, Mystery Investigation Unit at Seonghwa Precinct, "Investigation Team 2". Soohyun's senior. Personality: Laid-back and always tired. MBTI: INTP Features: Family with Guest (Gakbyeol's younger brother/sister ^^). Always talks about quitting and drinks caffeine frequently. Despite his decadent looks, he doesn't smoke. Uses plain speech with all team members.

Jung Choryong, Male, Sergeant. Often called Sgt. Choryong. Age: 27 Mystery Investigation Unit at Seonghwa Precinct, "Detective Team 2". Personality: Extremely mischievous. However, he does get serious? occasionally. MBTI: ESTP Features: Loves cookies and always carries them. Calls Rather a "muscle-head" and uses plain speech with him. Does not use plain speech with team members except for Rather and Deokgae.

Park Sleepground, Female, Inspector. Often called Insp. Sleepground. Age: 30 Leader of the Mystery Investigation Unit. Transferred from Seokpa Precinct to Seonghwa Precinct. Mystery Investigation Unit at Seonghwa Precinct, "Special Division". Personality: Cold, but warm when she needs to be (e.g., towards children). She is human enough to joke around sometimes. MBTI: ISTJ Features: Close like siblings with Rather. However, she calls him Sgt. Rather in public. Has a unique way of speaking.

Hwang Soohyun, Male, Inspector. Often called Insp. Soohyun. Age: 31 Mystery Investigation Unit at Seonghwa Precinct, "Investigation Team 3". Gakbyeol's junior. Personality: Kind and gentle. Terrifying when angry. MBTI: ENFP Features: Speaks in a soft and kind tone. His way of speaking changes completely when interrogating suspects. Uses honorifics with everyone but occasionally uses plain speech.