Kill Boksoon

A man lies half-naked on the cold ground, clutching a pillow. Wondering if he had left a hotel window open, he realizes he is on a bridge. Soon, the contract killer Gil Bok-soon wakes him. He is revealed to be Shinichiro Oda, a second-generation Korean-Japanese yakuza. Oda asks why she has not killed him yet. Bok-soon mentions her daughter Jae-young, recalling a moment when Jae-young criticized corruption and unfair competition. Seeking a fair fight, Bok-soon allows Oda to prepare his weapon, but when the duel begins, she abruptly abandons the rules, shooting him mid-battle. As Oda curses her in Korean, Bok-soon finishes him off.

After returning home, Bok-soon resumes her quiet domestic life. While doing laundry, she discovers cigarettes in Jae-young's clothes, triggering memories of a strict, abusive father who once forced her to eat a cigarette as punishment. Bok-soon smokes in silence, unable to confront her daughter about it when Jae-young returns. Meanwhile, her agency director Min-kyu assigns her a new contract, a choice between a foreign or domestic assassination. Worrying about Jae-young, Bok-soon picks the local job. The target is a prime minister nominee who staged his son's death as a murder-suicide to cover up a college admissions scandal. Realizing the target's guilt and his grief, she spares him and lies about the mission's failure.

Min-kyu grows suspicious, but Bok-soon insists it was a failure, supported by her intern Young-ji. Soon after, Jae-young stabs a classmate, Chul-woo, with scissors. At school, Bok-soon learns everyone involved refuses to talk, leaving Jae-young at risk of expulsion. Later, Jae-young confesses to her mother that she is a lesbian. She reveals the stabbing was retaliation against Chul-woo, who had secretly filmed her and her girlfriend So-ra, then blackmailed them. When he mocked their relationship, Jae-young lashed out in anger.

Amid these troubles, Young-ji visits Bok-soon after being fired. Bok-soon takes her to a friend's restaurant, where several fellow assassins, including her close colleague Hee-sung, arrive. It turns out Hee-sung had staged Bok-soon's failed mission to earn a promotion, manipulated by Min-kyu's sister Min-hee, who wants Bok-soon dead. The assassins turn on Bok-soon, but she kills them all in a brutal fight, sparing only Young-ji. Learning Hee-sung's betrayal was coerced, she ends his life herself and reports the cleanup. Furious, Min-kyu confronts her, forcing her to a new contract. After that, Min-kyu confront Young-ji and kills her.

Later, Bok-soon kills Min-hee in revenge and faces Min-kyu in a final confrontation. They feign civility but soon clash violently. Bok-soon manipulates Min-kyu's emotions and kills him, not realizing that his office CCTV was streaming live to a tablet delivered to Jae-young. When Bok-soon rushes home in horror, expecting trauma, she instead finds her daughter calm and affectionate. In the epilogue, Bok-soon tends her plants as news reports that the corrupt prime minister candidate has been found dead in an apparent suicide. Meanwhile, Jae-young, dressed in red like her mother, visits her school one last time, leaving cryptic, threatening words to So-ra and Chul-woo before walking away with confidence.

On January 4, 2022, Kill Boksoon confirmed production with the ensemble casting of Jeon Do-yeon, Sul Kyung-gu, Esom, and Koo Kyo-hwan as the lead roles.^[6] On April 7, 2022, it was reported that actress Jeon Do-yeon was injured while filming and stopped filming, but after receiving treatment at the hospital, she returned to the scene and continued filming.^[15]

The film had its world premiere in the Berlinale Special section of the 73rd Berlin International Film Festival on February 18, 2023.^[16] It was released on Netflix on March 31, 2023.^[5]

In September 2024, Netflix announced the casting of Yim Si-wan and Park Gyu-young for the film, Mantis, a character that is only mentioned in Kill Boksoon.^[22] The film was released on September 26, 2025 on Netflix.