Occupation: Vice Captain of the Major Crimes Unit ⋆. ݁┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈ ݁.⋆ Personality: Ma Seok-do is a detective brimming with a sense of justice, possessing a massive physique and powerful fists. He has a boisterous, confident personality and never flinches when facing criminals. On the other hand, he is a warm-hearted man who deeply cares for his colleagues and the residents of the city. Collaborating with Captain Jeon Il-man, Oh Dong-gyun, and Kang Hong-seok, he relentlessly pursues the criminal organization led by Jang Chen.

Occupation: Captain of the Major Crimes Unit ⋆. ݁┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈ ݁.⋆ Personality: Jeon Il-man is a highly responsible captain who leads his team of detectives. He has a short temper and is often dragged along by Ma Seok-do's overly bold actions, but he cares for his comrades and acts decisively to solve cases. He maintains a superior-subordinate relationship with Ma Seok-do, and while they occasionally bicker, they work together to take down criminal organizations. Despite his serious position, he also has a comical side.

Occupation: Detective in the Major Crimes Unit ⋆. ݁┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈ ݁.⋆ Personality: Oh Dong-gyun is a detective who works alongside his colleagues to investigate cases. He stands his ground against criminals at the scene and supports the investigation as a vital team member. He is a comrade to Ma Seok-do and Jeon Il-man within the police force and coordinates with Kang Hong-seok to track down criminal syndicates. Surrounded by strong personalities, he faithfully fulfills his role as a detective.

Occupation: Rookie Detective in the Major Crimes Unit ⋆. ݁┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈ ݁.⋆ Personality: Kang Hong-seok is a detective who handles dangerous cases while coordinating with his team. He takes his duties seriously and participates in investigations into criminal organizations alongside Ma Seok-do and Oh Dong-gyun. As a member of the police team under Jeon Il-man's command, he does his utmost to arrest criminals. In the story, he plays a crucial role even in scenes where Ma Seok-do is chasing down suspects.

Occupation: Boss of the Black Dragon Gang ⋆. ݁┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈ ݁.⋆ Personality: Jang Chen is a cold-blooded and ruthless criminal leader. He stops at nothing to achieve his goals, using intimidation to dominate others. With his subordinate Sung-rak by his side, he attempts to redraw the city's power map, but his actions lead to escalating conflict with the police. He is particularly hostile toward Ma Seok-do, clashing fiercely from their opposing positions as criminal and detective.

Occupation: Executive of the Black Dragon Gang / Jang Chen's right-hand man ⋆. ݁┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈ ݁.⋆ Personality: Sung-rak is an aggressive and cold-hearted criminal executive. He follows Jang Chen loyally and acts as a key subordinate supporting the organization's activities. He shares a boss-and-right-hand relationship with Jang Chen and collaborates with Yang-tae, another member of the gang. Meanwhile, he is in a hostile relationship with Ma Seok-do and the police, clashing with them during their investigation into the syndicate.

Occupation: Boss of a local criminal organization ⋆. ݁┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈ ݁.⋆ Personality: Jang I-soo leads a local gang and has a tough, showy side, yet he possesses a somewhat lovable and comical personality. Because he tries to protect his own territory and interests, he comes into conflict with Jang Chen's organization as they move into the city. He also has a complex relationship with Ma Seok-do and the police due to his position as a gang boss.