“Kingmaker” writer and director Byun Sung-hyun’s first entry into the action genre, “Kill Boksoon,” is a crime thriller centered on a mother raising her teenage daughter while working as a professional hitwoman.

Gil Bok-soon (South Korean superstar Jeon Do-yeon, most recently seen in rom-com series “Crash Course in Romance”) is a legend among the hitman industry, where assassins are contracted to hierarchical killing agencies and assigned jobs based on their letter grades.

Gil – dubbed “Kill Bok-soon” based on her 100 percent success rate starts her introduction in the movie during a hit job where she impress her yakuza-linked adversary . Bok-soon also takes time out of the homicidal gig to wax poetic about her 15-year-old Jae-young (Kim Si-a), who has inspired Bok-soon to exercise a bit more fairness within her brutal trade, including giving her yakuza target a fair fight before ensuring that she’ll get home to her daughter.

The rest of the movie follows the beats that are essential to crime thrillers: We meet Bok-soon’s formidable boss, MK Entertainment CEO Cha Min-kyu (Memoir of a Murderer’s Sul Kyung-gu), as well as her allies and frenemies, notably her C-ranked co-worker Han Hee-sung (“D.P.’s” Koo Kyo-hwan) and MK’s Director Cha Min-hee (“Taxi Driver’s” Esom).

A job goes wrong, giving those plotting against Bok-soon a chance to strike, and she protects herself in stunningly choreographed fight scenes, as she battles five opponents at once and evades hand-to-hand blows without breaking a sweat. The camerawork leads viewers through every step, frenetically moving around the thrust fists and thrown weapons in real time. Phew.

Simultaneously she is also dealing with some heightened motherhood drama, including Jae-young taking up smoking and getting suspended with the threat of expulsion from school.

The movie has some excellent writing around it’s characters and their development. Jeon balances the quiet confidence and bravado of Bok-soon at work with private moments of uncertainty and exasperation, only allowed when she’s alone or Jae-young’s head is turned. She is quite an actor as she completely transforms into a powerful, focused career woman unwilling to make sacrifices for her home life.

She also gets a talented scene partner in Kim, as the young actress plays a sardonic teen who’s forming her own firm beliefs about the world while also hiding a life-altering secret.

Kill Boksoon brings in deft social commentary in realizing the elaborate world of MK Ent. and the companies that offer killing services. The agencies include several references to the South Korean entertainment industry, with the most tongue-in-cheek inclusion the designation of hit jobs as “shows” and the introduction of Kim Young-ji (Lee Yeom), an ace trainee set to make her killing debut.

The intricate world-building is another level of care that sucks viewers into the film, while also fleshing out Bok-soon as a woman with extremely high stakes in all aspects of her life.

Chairman Cha Min-kyu, who runs the world of assassins with an iron fist that only seems to unclench for Bok-soon herself. Their relationship is maybe the most compelling of the film, with Min-kyu serving as the lifelong mentor who found Bok-soon as a 17-year-old protege. Jeon and Sul, who previously acted as husband and wife in the 2001’s “I Wish I Had a Wife” and 2019’s “Birthday,” keep the full span of their history mysterious, drawing viewers in with the question of just how much leeway the boss will give his favorite hire.

“Kill Boksoon” will make you rethink about assassins as humans.

Everything from the gorgeous sets to the captivating cinematography to the career highlight performance by Jeon  demands the audience’s attention, making this one of the most fun watches of Netflix’s year so far.