Queen Mantis

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Queen Mantis

사마귀: 살인자의 외출 (Samagwi: Sarinja-ui Oechul) · 2025 · South Korea

WriterLee Young-jong

DirectorByun Young-joo

Episodes8 eps · ~60 min each

⏱️ Binge Time8h 0m

AiredSep 5 – Sep 27, 2025

GenreThriller · Mystery · Crime

Content RatingTV-MA · Violence & Mature Themes

Netflix
Viki

Serial Killer
Psychological Thriller
Mother-Son
Copycat Killer
Dark Family Secrets

One box. Everything you need to decide.

Ko Hyun-jung leads a tightly wound ensemble — a killer, a son, and the shadows between them.

Ko Hyun-jung

Jung Yi-shin

Lead

Jang Dong-yoon

Cha Soo-yeol

Lead

Cho Seong-ha

Supporting Role

Supporting

Lee El

Kim Na-hee

Supporting

Kim Bo-ra

Lee Jung-yeon

Supporting

Han Dong-hee

Seo Ara

Villain

Lee Hwang-eui

Supporting Role

Supporting

Kim Min-ho

Supporting Role

Supporting

Kim Tae-jeong

Supporting Role

Supporting

Spoiler-light recaps — enough to remember where you left off, nothing that ruins the ride.

EP 01

The First Visit

September 5, 2025

A brutal murder in a residential area bears the unmistakable signature of “The Mantis” — a serial killer who has been locked away for two decades. Detective Cha Soo-yeol, who has spent his entire adult life running from his mother’s legacy, is assigned to the case. The episode’s final act delivers on its premise immediately: the meeting between son and mother in prison is cold, loaded, and deeply uncomfortable — exactly as it should be.

EP 02

Her Terms

September 6, 2025

Yi-shin agrees to cooperate — but only on her own terms, which she makes crystal clear from minute one. Her cryptic leads are immediately useful and immediately unsettling: no one should know this much about someone else’s psychology unless they’ve lived it. Soo-yeol tries to keep his professional distance, but the episode makes clear that his resentment and his need are fighting each other in every scene.

EP 03

What She Knows

September 12, 2025

Soo-yeol races to prevent another killing as Yi-shin’s knowledge of the copycat’s methods grows more precise — and more suspicious. The episode begins peeling back Yi-shin’s past: the domestic violence, the institutional failures, the circumstances that preceded “The Mantis.” Ko Hyun-jung is extraordinary in the flashback sequences — this is the episode where her performance shifts from compelling to essential.

EP 04

The Shape of the Past

September 13, 2025

The investigation turns inward — into Yi-shin’s history, and into Soo-yeol’s own suppressed memories. Yi-shin begins applying quiet psychological pressure, forcing her son to confront truths about their shared history that he has spent decades burying. Meanwhile, the murders reveal a pattern that isn’t random: each victim is a deliberate message, and someone has been planning this for a very long time.

EP 05

Closer to Home

September 19, 2025

The threat escalates — this time into territory that hits too close to Soo-yeol personally. His wife Jung-yeon begins to sense that something is deeply wrong, and the cracks in their marriage widen under pressure he can’t explain without revealing everything. Yi-shin watches from behind glass, always measuring, always two steps ahead. The episode ends on a turn that makes clear the copycat isn’t just mimicking the past — they’re rewriting it.

EP 06

The Phone Call

September 20, 2025

Yi-shin takes over a critical phone call with the copycat — and the result is one of the most riveting scenes in the drama. She doesn’t just gather information; she gets inside the caller’s head with a precision that is terrifying and brilliant in equal measure. The moral ambiguity that the show has been building arrives in full force: Yi-shin is invaluable, but the episode quietly confirms she has known more about this copycat than she ever let on.

EP 07

The Hostage

September 26, 2025

Jung-yeon finally learns the truth about Soo-yeol’s birth mother — and the revelation fractures what remained of their marriage. The copycat escalates dramatically, taking a hostage and placing Soo-yeol in an impossible position that tests every boundary he has held onto. Yi-shin watches the developments from prison with an expression that gives nothing away — the show’s most inscrutable moment, played to perfection.

EP 08

What She Took

September 27, 2025

The finale delivers on every question the show has been building toward — and then complicates the answers in ways that feel earned rather than cheap. The copycat’s identity is revealed. The confrontation between Yi-shin and her protégé is brutal and deeply sad. And in the drama’s most pivotal moment, a mother makes a choice that redefines everything that came before it. The final frame is deliberately unresolved — haunting in the best possible way.

Full spoilers ahead — everything that happens in the finale and what it all means.

The copycat is revealed, and it changes everything. After the harrowing hostage exchange that closes episode 7, the finale opens with Yi-shin finally coming face to face with the person who has been recreating her crimes: Seo Ara (Han Dong-hee), a woman who witnessed Yi-shin’s killings as a child and didn’t experience them as horror — she experienced them as salvation. Seo Ara watched The Mantis kill abusive men, and what she saw was a savior. She built her entire identity around that image, and spent two decades waiting for a chance to follow in Yi-shin’s footsteps.

Yi-shin confronts her protégé directly — and wins. The confrontation between Yi-shin and Seo Ara is the emotional and narrative centerpiece of the finale. Yi-shin doesn’t lecture or moralize. She moves with the same terrifying efficiency she demonstrated twenty years ago, overpowering Seo Ara and stabbing her in a climax that is brutal, decisive, and deeply complicated. The show refuses to make this a clean heroic moment: Yi-shin is still a killer, and she kills here. The difference is motive — and whether that difference matters is a question the drama leaves open.

The moment that redefines the entire series. What happens next is Queen Mantis at its most emotionally precise. Soo-yeol, having uncovered the full truth about his family’s history — including the identity of Yi-shin’s father and the violence that preceded her crimes — is on the edge of killing the old man himself. Yi-shin intervenes physically, stopping her son from crossing a line she crossed herself. Then, in the fire that follows, she kills her father on his behalf — taking the sin onto herself so Soo-yeol remains clean. A mother who murdered five men, choosing to protect her son from becoming what she became.

Soo-yeol’s reckoning — and the limits of understanding. In the aftermath, Soo-yeol doesn’t find peace. He finds clarity, which is a different and harder thing. He understands now, for the first time, the full dimensions of what his mother did and why — the violence that preceded her crimes, the systemic failures that surrounded her, the choice she made to take the law into her own hands. Understanding doesn’t mean forgiveness. But it means he can finally stop running from a story he was always part of.

The open ending — and what it means. The finale closes without confirming Yi-shin’s fate. She survives the fire, but the final frame leaves her status — imprisoned, free, alive, dead — deliberately unresolved. It is a haunting choice, and the right one. Queen Mantis was never a story about justice or punishment. It was a story about what we inherit from the people who raised us, and whether it’s possible to carry that weight without being defined by it. The answer the show gives is not yes or no — it’s a final image that asks the audience to sit with the question long after the credits roll.