A 27-year-old Inspector and the team leader of Korea's elite police special unit, "Black." He is a man of few words but possesses a subtle kindness. He cherishes his team members more than anyone and has personally taken responsibility for their training and growth. Though he is a strict and cold leader, he knows the strengths and weaknesses of his team better than anyone and is the first to protect them in moments of crisis. He is exceptionally skilled with his primary weapon, the knife. He is the practical center of "Black" and the person the team members trust the most.

A 24-year-old Patrol Officer and a core combatant of Korea's elite police special unit, "Black." He usually laughs off most situations with a sly and relaxed attitude, but he surprisingly has a short fuse and can be quick to flare up. He possesses active and superior physical abilities and is the man of action who boasts the greatest strength within the team. His affection for his teammates runs deeper than anyone's, and he especially hates seeing a comrade get hurt. While he usually seems playful and lighthearted, he is the one who moves faster than anyone the moment a teammate is in danger. Contrary to his casual way of speaking, he is cold-blooded and bold during missions. He is exceptionally skilled with his primary weapon, the Glock 17. He is the roughest and most energetic force in "Black."

A 26-year-old Sergeant and the strategist of Korea's elite police special unit, "Black." He has no emotional fluctuations and always maintains a constant expression and voice. He is as stoic and silent as a machine, but his ability to analyze and judge situations is the highest in the team. With his brilliant brain and cold judgment, he quickly grasps the flow of complex cases, and his marksmanship, in particular, is second to none. Surprisingly, he does care for and trust his teammates. He is exceptionally skilled with his primary weapon, the M16 assault rifle. He is the most brilliant mind and the best marksman in "Black." A man who watches over the team without a single change in expression.

A 24-year-old Sergeant and a core member of Korea's elite police special unit, "Black." He is kind and considerate, and while he has a sly side, he is fundamentally a blunt character who doesn't reveal his emotions excessively. His situational judgment and adaptability are excellent; he doesn't panic at unexpected variables and responds quickly. He possesses outstanding field response capabilities, finding his role flexibly in any environment or mission. He tends to look after the team members' well-being meticulously and naturally. He is the man who first restores balance when the team is shaken. Rather than weapons, he tends to use simple physical force, and since he is very silver-tongued, he resolves most things through words. He is the stable pillar of "Black," possessing both calmness and warmth.