Netflix’s latest Korean action thriller Mantis premiered on September 26, delivering brutal action and complex character dynamics in the expanded Kill Boksoon universe. While the film showcases impressive fight choreography and stellar performances, does this spin-off live up to its predecessor’s legacy? Let’s dive into the explosive ending and what it means for the assassin underworld.

Mantis Final Showdown: Power Struggle at MK Enterprise

The climax of Mantis unfolds in a brutal three-way battle that determines the future of the contract killer industry. After a series of betrayals and manipulations, three key players converge for the ultimate confrontation:

Han-ul (Mantis) – Elite assassin torn between loyalty and love Jae-yi – Ambitious killer seeking to prove her worth
Dok-ko – Veteran founder of MK Enterprise refusing to relinquish control.

The showdown takes place in Dok-ko’s office, where years of resentment and ambition explode into violence. Despite Han-ul’s reluctance to kill his mentor, Dok-ko insists the fight must end in death. In a tearful moment that caps her character arc, Jae-yi delivers the fatal blow, ending Dok-ko’s reign.

Character Arc Analysis: From Rivalry to Revolution

Character	Beginning	Arc Development	Final Position
Han-ul (Mantis)	Top assassin, loyal to MK	Torn between mentor and love	Chooses independence
Jae-yi	Expelled assassin, insecure	Rises through manipulation	Takes control of MK Enterprise
Dok-ko	Retired founder seeking return	Manipulates former protégé	Dies fighting for power
Benjamin	Software mogul with grudges	Uses Jae-yi for revenge	Eliminated by his own pawn

Jae-yi’s Strategic Victory: More Than Just Survival

Jae-yi’s triumph represents more than winning a fight—it’s a masterclass in strategic thinking. Throughout the film, she systematically:

Exploited Benjamin’s Resources: Used his funding while planning his elimination
Leveraged Han-ul’s Feelings: Turned his protective instincts into an advantage
Outmaneuvered Dok-ko: Combined with Han-ul to overwhelm the veteran

Her final move—hiring Mantis Company to assassinate Benjamin—demonstrates her complete control over the situation. She transforms from an expelled outcast to the undisputed leader of the assassin world’s most powerful organization.

Netflix’s Ambitious Expansion: Kill Boksoon Universe

Mantis serves as Netflix’s attempt to expand the Kill Boksoon universe, similar to how Marvel builds interconnected stories. The film premiered on Netflix on Friday, September 26, 2025, at 4 pm KST, marking director Lee Tae-sung’s feature debut on the platform.

The connection to Kill Boksoon goes beyond shared universe elements. The biggest treat is Jeon Do-yeon’s cameo as Gil Boksoon, appearing briefly to give advice to Mantis, a moment sure to delight fans.

Performance Highlights: Stellar Cast Elevates Material

The film’s strongest asset lies in its performances, particularly:

Im Si-wan brings depth to Han-ul, balancing the character’s deadly skills with emotional vulnerability. His portrayal of an assassin struggling with loyalty creates the film’s emotional core.

Park Gyu-young delivers a powerhouse performance as Jae-yi, showcasing her character’s evolution from insecurity to ruthless ambition. Her final scenes demonstrate remarkable range.

Choi Hyun-wook steals scenes as Benjamin, whose portrayal of a privileged, spoiled, dangerously unpredictable businessman is both hilarious and captivating.

Critical Assessment: Action Excellence Meets Story Struggles

While Mantis excels in several areas, it faces significant storytelling challenges:

Strengths:

Exceptional action choreography and cinematography
Strong performances across the cast
Impressive production values matching Kill Boksoon’s quality
Effective expansion of the assassin world mythology

Weaknesses:

Nearly two-hour runtime drags, weighed down by a plot that feels disjointed and slow
The narrative lacks coherence, leaving the overall experience tedious and unfulfilling
Pacing issues that prevent building proper tension

Global Streaming Impact and Future Prospects

Mantis is a 2025 South Korean action thriller film co-written and directed by Lee Tae-sung in his feature debut for Netflix, representing Netflix’s continued investment in Korean content following global successes like Squid Game and Kill Boksoon.

The film’s reception will likely determine whether Netflix continues expanding this particular universe or focuses on developing new Korean action properties. The assassin genre remains popular globally, with audiences craving stylized action and complex characters.

Is Mantis Worth Your Time?

For most viewers, it can be considered a one-time watch rather than a must-see. However, Mantis may hold some appeal for those invested in the cinematic universe of Kill Boksoon.

The film succeeds as a showcase for impressive action sequences and strong performances but struggles to establish itself as essential viewing beyond its connection to Kill Boksoon. Fans of the original will find enough to appreciate, while newcomers might struggle with pacing and narrative issues.

Final Verdict: Mantis delivers on action and performances but falls short of creating a compelling standalone story. It’s a decent addition to the Kill Boksoon universe that suggests potential for future installments if storytelling improves.

Watch Mantis exclusively on Netflix and experience this brutal expansion of the Kill Boksoon assassin world.

Frequently Asked Questions

Q: Do I need to watch Kill Boksoon before watching Mantis?

A: While Mantis is set in the same universe as Kill Boksoon, it functions as a spin-off with new characters and storylines. However, watching Kill Boksoon first will enhance your understanding of the assassin world’s rules and provide context for Gil Boksoon’s cameo appearance.

Q: Will there be more films in the Kill Boksoon universe after Mantis?

A: Netflix hasn’t officially announced additional films in the Kill Boksoon universe yet. The future likely depends on Mantis’s performance and audience reception. Given Netflix’s investment in Korean content and the popularity of action thrillers, more installments remain possible if there’s sufficient demand.