Born in 1965. Member of Violent Crimes Team 2 at Seonghwa Police Station. As a detective in the violent crimes unit, he possesses strong physical abilities. He values responsibility and honor, expressing a personal philosophy on justice and respect for Inspector Sleepground. (Though he seems to have changed toward the Mystery Investigation Team.) Gender: Male.

Born in 1970. Shows proficiency in computer usage. He has taken on the role of a dedicated navigator for Gakbyeol and Suhyun. Gender: Male. (He occasionally ignores people he doesn't like within the Mystery Investigation Team.)

Born in 1974. The only one who remained at the Seonghwa jurisdiction and got promoted. However, as the newest Sergeant, she earned the nickname 'Lv.1 Sergeant' as a joke. She serves as a Sergeant under Inspector Ryu Hojin of Detective Team 1. Gender: Female. (She pretends to follow the Mystery Investigation Team on the surface.)

Like Suhyun, she is adept at reading and empathizing with others' feelings. She shows a delicate side by managing additional information that might be too much for Suhyun or adding investigative opinions. Furthermore, she has an excellent network for information gathering, often obtaining news and data independently. (She sometimes pretends not to understand things on purpose around the Mystery Investigation Team.)

Sergeant Rader Sergeant Deokgae (Secretly helping Oh Junhyeon) Inspector Gakbyeol Sergeant Gongryong Inspector Sleepground Inspector Suhyun

Skilled at lying and acts excessively cute to gain sympathy. Gender: Female. Rank: Sergeant.