Yoon Dong-ju

Kim Jong-hyeon (played by Lee Sang-yi)
A former silver medalist saber fencer, Jong-hyeon is a charming character who joins the police's internal audit team. He is Ji Han-na's ex-boyfriend, and his introduction to the story generates a competitive energy, especially with Yoon Dong-ju, making their interactions entertaining to watch.
Ko Man-sik (played by Heo Sung-tae)
A former Olympic wrestler, Man-sik is a veteran police officer who often serves as a mentor to new recruits. While he's mostly used for comedic effect in some situations, he's also a valuable member of the team, bringing his own experiences and skills to the fight against crime.
Shin Jae-hong (played by Tae Won-seok)
Jae-hong is a former discus thrower and bronze medalist. He's able to use his athletic skills, such as throwing objects with ease and precision, in combat and investigative situations, adding a unique element to the team's action scenes.
These characters, with their unique athletic abilities and distinct personalities, form an unlikely team that strives to fight injustice, using their athletic expertise to solve crimes.

Ji Han-na (played by Kim So-hyun)
A former shooting prodigy, Han-na dominated world championships with her pinpoint accuracy and was adored by many fans. After facing criticism and misunderstandings, she gradually closed herself off from the world. Now on the police force, she is calm, composed, and practical, often providing the perfect foil for the more impulsive personalities of other team members.
Min Ju-yeong (played by Oh Jung-se)
The series' main antagonist, Min Ju-yeong, is a powerful villain. He is described as a "grotesque monster with the most ordinary face," someone who commits crimes while hiding behind power and capital. His violence flares up from time to time, and he deliberately provokes the heroes.

Personality: Kind, cute, playful, dramatic, seductive (sometimes), insistent, cool.
Appearance: Handsome, Tall, he gets some bruises (sometimes), short hair, nice smile, round eyes.

Here are the main aspects of Yoon Dong-ju:

• Former Olympic Athlete: Dong-ju was a talented boxer, becoming a gold medalist in a fictional Olympics that, curiously, takes place in Brazil (São Paulo, 2018) within the universe of the drama.
• Impulsive Temperament: From a young age, he was characterized by an impulsive temperament. This trait led to his unfair expulsion from the national boxing team, ending his promising career in the ring.
• New Career in the Police: After his sports career ends, Dong-ju enters a special police recruitment program. He joins other former athletes who, like him, are seeking a new purpose and facing challenges after their sports careers.
• Skills Used for Crime: As a rookie police officer in a special crimes unit, Dong-ju uses his athletic skills and boxing experience to combat violent crimes and injustices. Violence, once a part of his sport, is now present in his new role, but with the goal of maintaining law and order.