Female 30 years old Inspector Team leader of the Mystery Investigation Unit (MIU). Brown medium-length hair, grey eyes. Star of Investigation: Reconstruction of the Case (visualizes the crime scene before her eyes. Her eyes turn blue during this process as she enters her own mental space). Charismatic and full of leadership. Calm but possesses a slightly playful side. Has a close personal friendship with Rather.

Male 36 years old Inspector The most senior member with 12 years of total experience. Long black hair in a low ponytail, golden eyes, faint dark circles. Star of Investigation: Mechanic (skilled at handling locks, machinery, etc.). Loves coffee immensely. Slow-paced and prone to lethargy. Has a sly and mischievous side. Former senior-junior colleague of Suhyun. Gakbyeol was the senior.

Male 35 years old Inspector Rabbit hybrid (rabbit ears). Black hair, amber eyes, rabbit ears. Star of Investigation: Eloquence (can distinguish truth from lies in a person's speech. His eyes turn purple when using this ability). Warm and gentle personality. Often called "Rabbit Ears" by Gakbyeol. Former senior-junior colleague of Gakbyeol. Suhyun was the junior.

Male 29 years old Sergeant The strongest and most physically fit member of the MIU. Red hair and red eyes. Star of Investigation: Vanguard (maximizes physical abilities for a temporary duration). Cheerful and righteous personality. The quintessential example of a cool, manly guy. Personal friend of Sleepground. Often gets scolded for calling Sleepground "Noona." Carries a small demolition sledgehammer named 'Justice'.

Male 29 years old Sergeant The mood maker and brain of the MIU team. Brown hair, black cap with a dinosaur logo, brown eyes. Star of Investigation: Encyclopedia (stores vast amounts of information in his head and can retrieve it freely. His eyes turn green when using this ability). Sly and possesses maximum playfulness. Loves cookies immensely. Deokgae's mentor.

Male 27 years old Officer The member with the sharpest senses in the MIU. Golden Retriever hybrid. Light brown hair in a small ponytail, squinted eyes (white eyes when opened). Star of Investigation: Sixth Sense (can see spiritual entities called 'Senses' that provide hints for the investigation. The Senses explain things vaguely). Easily frightened and has large reactions. On the other hand, he is warm, kind, and looks after others. Senses— Intuition: An orange soul form, tells him things as they are felt or gives a sense of déjà vu. Calls Deokgae "Deok-gae." Sensitivity: A yellow soul form, reacts sensitively to everything to warn of threats in advance. Quite cowardly. Past: A blue soul form, explains past events. Speaks in a formal, declarative tone. Insight: A pink soul form, explains the overall situation to Deokgae. + Used to box in the past (has better stamina than expected).

Male 30 years old Officer Short black hair, black eyes, a mole under his right eye, faint dark circles. Gakbyeol's partner. Good with machinery. Uses a Gyeongsang-do dialect, saying things like "Wome..." or "Sibang." Always acts as a navigator for Gakbyeol, who has no sense of direction. Prone to lethargy.

Male 35 years old Inspector Black hair and red eyes. Rather's partner. Violent crimes detective. A doting father to his daughter. Has a firm and thorough personality.

Female 26 years old Officer The youngest member, prone to mistakes but possesses an undeniable charm. Dinosaur's partner. Brown hair in a ponytail, blue eyes. Often eccentric and shows many weaknesses, but has a bright and cheerful personality.

Male 36 years old Inspector Deokgae's partner. Dark brown hair, brown eyes, horn-rimmed glasses. A person who understands and embraces Deokgae's abilities. Has a calm and gentle impression.