[Kdrama] Mercy For None Plot Summary Ending Explained & Cast & Filming Location 2025

Mercy for None is a gripping noir action series set in the ruthless underworld of Seoul, marking the return of So Ji-sub to the action genre after a long hiatus. Inspired by the popular Naver webtoon, the story centers on Nam Gi-jun, a former top enforcer who once severed his own Achilles tendon to escape the criminal life. Eleven years later, the mysterious death of his younger brother, Nam Gi-seok, drags him back into a world of violence, betrayal, and revenge. Armed with nothing but a baseball bat and a burning desire for justice, Gi-jun cuts a bloody path through the city’s rival gangs—Juwon Group and Bongsan Group—uncovering secrets, lies, and the true cost of power.

Director Choi Sung-eun, known for her atmospheric and character-driven storytelling, leads a remarkable cast, including So Ji-sub, Heo Joon-ho, Ahn Kil-kang, Lee Beom-soo, Gong Myung, Chu Young-woo, Jo Han-chul, and special appearances by Cha Seung-won and Lee Joon-hyuk. The production team, including screenwriter Yoo Ki-sung and original webtoon creators Oh Se-hyung and Kim Kyun-tae, delivers a visually striking and emotionally charged series that stays true to the source material while elevating its cinematic impact. The series was shot across iconic locations in Seoul, including Gangnam, Itaewon, and Incheon, as well as Busan’s Gamcheon Culture Village and Jagalchi Fish Market, providing a dynamic backdrop for its intense action and dramatic confrontations.

Casting was a highlight, with So Ji-sub being the top choice for fans of the original webtoon. Director Choi Sung-eun praised the entire cast as “unbelievable,” emphasizing So Ji-sub’s ability to convey deep emotion and physicality, and expressing gratitude for the creative freedom the talented ensemble allowed. The production process was marked by a collaborative atmosphere, with actors frequently improvising and sharing ideas, resulting in authentic performances and memorable on-screen chemistry. The action choreography is raw and realistic, with So Ji-sub reportedly treating fight scenes as a form of dialogue, ensuring every punch and movement carries emotional weight.

Mercy for None stands out as a masterclass in Korean noir, blending brutal action, complex characters, and a plot that twists and turns unpredictably. The series is not for the faint of heart, but for those who crave intensity, emotional stakes, and a story that lingers long after the credits roll.

Mercy for None Netflix

Korean 광장 | Japanese 広場 | ดับแค้นไร้ปราณี
Genre Action, Crime, Noir
Episodes 7
Release Date June 6, 2025 | Release Time 16:00 (KST)
Director Choi Sung-eun | Screenplay Yoo Ki-sung
Adaptation Original webtoon “광장” by Oh Se-hyung, illustrated by Kim Kyun-tae
Production Studio Dragon, Netflix
Cast So Ji-sub, Heo Joon-ho, Ahn Kil-kang, Lee Beom-soo, Gong Myung, Chu Young-woo, Jo Han-chul, Cha Seung-won (special appearance), Lee Joon-hyuk (special appearance)
Music OST by various artists
Martial Arts Realistic hand-to-hand and melee combat choreography
Filming Period October 2023 – March 2024
Production Company Studio Dragon, Netflix
Distributor Netflix
Premiere Date June 6, 2025 | Runtime 42 minutes per episode
streaming Netflix

[Kdrama] Mercy for None Plot Summary Ending explained & cast & filming location 2025

Mercy for None Cast

Nam Gi-jun (So Ji-sub): A man who had left the underworld and lived in seclusion for 11 years, but returns to the organization to seek revenge after his brother’s mysterious death.

Filmography: Sorry, I Love You (2004), Alienoid: Return to the Future(2024), Alienoid (2021)

Lee Joo-woon (Heo Jun-ho): The charismatic leader of the Juwon organization.

Filmography: Silmido (2003), Escape from Mogadishu (2021), Kingdom Season 2 (2020)

Goo Bong-san (Ahn Gil-kang): The head of the Bongsan organization, a key figure in the power struggles within the underworld.

Filmography: New World (2013), The Outlaws (2017), Queen Seondeok (2009)

Shim Sung-won (Lee Beom-soo): A professional fixer within the organization, adding tension to the story.

Filmography: IRIS (2009), Descendants of the Sun (2016), THE ROUNDUP : PUNISHMENT (2024)

Goo Jun (Gong Myung): The ambitious and vengeful heir to the Bongsan organization.

Filmography: Mr. Sunshine (2018), The Uncanny Counter (2020), Second Shot at Love (2025)

Lee Geum-son (Chu Young-woo): An elite prosecutor deeply involved with the organization, walking a tightrope between law and power.

Filmography: It’s Okay to Not Be Okay (2020), Sweet Home (2020), The Devil Judge (2021)

Cha Young-do (Cha Seung-won): A mysterious figure who does not belong to any organization, but whose presence has a significant impact on the world.

Filmography: Uprising (2024)

Choi Sung-chul (Jo Han-chul): Joo-woon’s right-hand man, striving to maintain balance within the organization.

Filmography: Mr. Sunshine (2018), Happy Ending (2023), Gyeongseong Creature (2023)

Nam Gi-seok (Lee Joon-hyuk): Nam Gi-jun’s younger brother and the organization’s second-in-command, whose mysterious death becomes the focal point of the incident (special appearance).

Filmography: THE ROUNDUP : NO WAY OUT (2023)

Director Choi Sung-eun is known for her atmospheric, character-driven approach, with previous works including “Little Sister.” She emphasizes emotional authenticity and visual storytelling, allowing actors creative freedom and encouraging improvisation for more natural performances. The cast’s chemistry and director’s vision combined to create a series that is both visually striking and emotionally resonant.

Mercy for None Plot Summary

In 2010, a fight breaks out in Yeouido, Seoul, and the brothers Nam Ki-joon and Nam Ki-seok appear on the scene. Nam Ki-joon (played by So Ji-sub) gets out of the car and heads somewhere…

Meanwhile, in another part of the city, a one-on-one showdown between a different gang and the Gu-un group is taking place. Joo-an is getting beaten up by the opposing gang’s fighter, but just as it seems he’s about to lose, So Ji-sub appears. After briefly greeting Lee Ju-un (played by Huh Joon-ho), the fight resumes, and So Ji-sub wins easily.

Meanwhile, Nam Ki-seok appears, seemingly captured somewhere…

Bong-san chairman Gu Bong-san (played by Ahn Gil-kang) meets with Ju-un chairman Lee Ju-un and asks for a favor regarding a family matter. It turns out Bong-san’s son has caused trouble, and in exchange for resolving the issue, he offers to hand over a Yeouido building lot. Initially refusing, Lee Ju-un, tempted by the land, eventually agrees and assigns the task to Nam Ki-seok (played by Lee Joon-hyuk). Ki-seok is reluctant but follows the boss’s orders.

Ki-seok then goes to meet Gu Jun-mo, Bong-san’s son, who had used foreign thugs to eliminate the head of Bong-san Group. Ki-seok gives the foreign thugs three days to leave, but when Jun-mo taunts him by mentioning his older brother Ki-joon, Ki-seok immediately punches him.

Later, unlike usual, Ki-seok goes to visit Ki-joon in the mountains but just looks at his face and leaves without a word. Upon returning home, the lights in Ki-seok’s entranceway suddenly flicker on and off. Sensing something odd, he looks around and is ambushed by a gang of assassins. Ki-seok manages to subdue them all, but in a moment of carelessness, he is stabbed and dies a meaningless death.

Upon hearing the news of Ki-seok’s death, Nam Ki-joon rushes to the scene. Meanwhile, the chairmen of Bong-san and Ju-un meet to discuss countermeasures. When Ki-joon appears at the meeting, he reminds them of the promise made 11 years ago to keep Ki-seok alive, then turns and leaves.

Suppressing his anger, Ki-joon immediately begins investigating Ki-seok’s death. He confronts the suspects and confirms that one of them has a younger brother, whom he uses as bait to lure out the others. A group of young gangsters boldly attacks Ki-joon at a PC room, but they are no match for Korea’s greatest fighter. However, it turns out that these were not the ones who killed Ki-seok. As Ki-joon tries to enter his home, he realizes someone is inside.

“Who are you?”

Chairman Lee Ju-un orders Cha Young-do (played by Cha Seung-won) to investigate Ki-seok’s death. Lee Ju-un’s son, prosecutor Lee Geum-son, is an outsider both in the Ju-un organization and in the prosecutor’s office. It is revealed that he has been secretly wiretapping his father and preparing warrants for both Ju-un and Bong-san.

Chairman Gu Bong-san and Chairman Lee Ju-un are on high alert with Nam Ki-joon’s return. They try to calm him down, but it doesn’t work. Realizing his son Jun-mo is in danger, Gu Bong-san offers all conditions to persuade Lee Ju-un.

Returning home, Gu Bong-san questions his son about Ki-seok’s death and learns that Jun-mo was responsible. Nam Ki-joon goes to the hotel where Jun-mo is staying. Jun-mo, who finally witnesses the legendary Nam Ki-joon’s fighting skills firsthand, tries to escape but remains defiant.

On his way back, Jun-mo learns from Chun-seok that it was Nam Ki-joon who founded both Ju-un and Bong-san. However, Jun-mo thinks this is an exaggeration and sends foreign assassins after Ki-joon. Both are quickly killed by Ki-joon, who then answers Jun-mo’s call.

“Wait, I’ll be there soon.”

Meanwhile, Bong-san desperately tries to save his son by meeting even Cha Young-do. But Jun-mo hires MMA champion Jeong In-seok as a bodyguard and goes outside, where he kills Ki-joon’s friend Choi Byung-ho on the spot and even kills Kim Chun-seok, who tries to stop him.

Excited, Jun-mo calls Nam Ki-joon and lures him to a house in Yangpyeong, gathering all the local thugs and offering a bag of money for capturing Ki-joon. He promises to share power in Bong-san. But Ki-joon defeats them all, and a bloody fight with Jeong In-seok ensues.

Has Ki-joon exhausted too much energy? For the first time, he is beaten badly by Jeong In-seok and is almost killed. But luck is still on Ki-joon’s side. He stabs Jeong In-seok in the eye with a piece of glass and turns the tide. Jeong In-seok is defeated, and even though Jun-mo pleads for his life, Ki-joon is unmoved and kills him.

Meanwhile, the Ju-un group is under pressure from the prosecutors. Jun-mo, desperate due to his son’s problems, requests a meeting with Chairman Lee Ju-un. As tensions rise between the two organizations, Lee Ju-un notices money missing from his account and confronts Cha Young-do.

Cha Young-do reveals Lee Geum-son’s true nature.

Eventually, a bloody fight breaks out between Gu Bong-san and Lee Ju-un. Lee Ju-un’s ambush succeeds, and Gu Bong-san is killed. Meanwhile, Cha Young-do quietly watches everything. With Bong-san dead, Ki-joon confronts Lee Ju-un for the truth, and Lee Ju-un confesses Cha Young-do’s involvement.

With Bong-san gone, Cha Young-do urges Lee Geum-son to become the new leader of Ju-un. Lee Geum-son declares to his father that he will take over Ju-un. Everything seems to be going according to Cha Young-do’s plan.

But Nam Ki-joon is still out there.

As Lee Geum-son prepares to take over Ju-un, Cha Young-do personally kills Chairman Lee Ju-un. Meanwhile, Nam Ki-joon arrives at Lee Ju-un’s place and is unexpectedly framed for the murder and arrested. Only then does he realize that Mr. Kim is actually Cha Young-do.

Ki-joon is interrogated, and Cha Young-do hints that there is another person involved.

Just when it seems everything is over, Ki-joon, still handcuffed, subdues the police and survives. Surprisingly, Shim Sung-won (played by Lee Bum-soo) helps Ki-joon. In the end, Cha Young-do is revealed to be the mastermind.

Meanwhile, Lee Geum-son, sensing something suspicious about Cha Young-do, orders a raid on Cha Young-do’s police station. Lee Geum-son realizes Cha Young-do killed his father and acts first. Cha Young-do, now in danger, tries to call for help, but Lee Geum-son has already taken control.

The eight-month-long game of deception between Lee Geum-son and Cha Young-do comes to an end. What is Lee Geum-son’s real plan?

Netflix Mercy for None Ending

Meanwhile, Cha Young-do, who had pretended to be defeated by Lee Geum-son, had secretly recorded everything. Gu Bong-san’s funeral is held, and Shim Sung-won is killed by assassins sent by Lee Geum-son. At the same time, assassins arrive for Nam Ki-joon, who is still recovering from his injuries and is in danger.

Just as he is about to be killed by the skilled assassin, Ki-joon, in a near-death state, blocks the assassin’s knife with his hand and delivers the finishing blow. Cha Young-do appears before the barely alive Ki-joon, holding a gun, and tries to persuade him to become the new leader of Gwangjang, but Ki-joon refuses.

After defeating Cha Young-do, Ki-joon heads to Lee Ju-un’s funeral. He appears before Lee Geum-son, warns him to handle the funeral properly, and leaves. The next day, as Lee Ju-un’s cremation proceeds, Ki-joon visits his brother Ki-seok’s funeral.

He hands over all the evidence to Haebom and asks him to handle the aftermath.

Meanwhile, Lee Geum-son prepares for the merger of Ju-un and Bong-san. Just as he is about to align with the political world, his corruption is exposed and all his plans fail. In his frustration, Lee Geum-son kills someone, but Choi Sung-chul barely manages to calm him down.

Finally, Nam Ki-joon appears, barely able to stand.

Just as a bloody fight is about to break out, Choi Sung-chul appears and dismisses all the bodyguards. Choi Sung-chul begs Ki-joon to stop for the sake of the organization, but Ki-joon refuses. Meanwhile, Lee Geum-son prepares a gun to protect himself.

Choi Sung-chul tries to trick and ambush Ki-joon but fails and is killed. Lee Geum-son tries to persuade Ki-joon but fails and shoots him. Despite being shot, Ki-joon does not fall, and Lee Geum-son, giving up everything, tries to kill himself but fails and dies from excessive bleeding.

As Ki-joon slowly dies, memories of his brother Ki-seok come to mind.

Interpretation of the Ending of Mercy for None

The Korean version of John Wick, Nam Ki-joon, continues to fight even in a near-death state. If you look closely, he avoids fatal blows and delivers the final strike to his opponent—a style of combat that is both desperate and calculated. Through this “give up flesh, take bone” fighting style, Ki-joon ultimately becomes the last one standing, making for exceptionally well-crafted action. Despite being hit by critical blows from opponents like Jeong In-seok, Choi Sung-chul, and Cha Young-do, he survives until the very end—truly a Die Hard-style action.

Who is the Real Culprit in Netflix’s “Mercy for None”? Cha Young-do? Lee Geum-son?

Who really killed Nam Ki-joon? Was it Gu Jun-mo, or was it Cha Young-do, who pulled the strings from behind? Or was it Lee Geum-son, who orchestrated the whole scheme? In a sense, all of them are culprits, but ultimately, the real “killer” is Nam Ki-joon himself, who left his younger brother behind despite knowing that he would inevitably be caught up in the organization’s war. That’s why the ending shows Ki-joon blaming himself.

This may seem odd, but it’s a characteristic of noir: even though it’s clear that there can never be peace between organizations, the strongest, Ki-joon, chooses to leave. In the end, the peace maintained for ten years by Cha Young-do and Lee Geum-son is shattered, and Ki-joon becomes a victim, caught up in their schemes.

Mercy for None Filming Locations

Savina Museum Address: 7, Yulgok-ro 10-gil, Jongno-gu, Seoul
National Assembly Building Address: 1, Uisadang-daero, Yeongdeungpo-gu, Seoul
Yongsan International Business District Address: 405, Hangang-daero, Yongsan-gu, Seoul
Daewonjeongsa Address: 675, Bukhangang-ro, Joan-myeon, Namyangju-si, Gyeonggi-do
Volvo Cars Dongdaemun Showroom Address: 117, Wangsimni-ro, Seongdong-gu, Seoul
Sungshin Women’s University Unjeong Green Campus Address: 97, Cheongseok-ro, Paju-si, Gyeonggi-do
Buk Seoul Dream Forest Address: 173, Wolgye-ro, Gangbuk-gu, Seoul
Seo Incheon 25 Baseball Center Address: 167-2, Cheongna-dong, Seo-gu, Incheon
Songdo Central Park Hotel Address: 15-23, Songdo Science-ro 16beon-gil, Yeonsu-gu, Incheon

Box Office Performance

“Gwangjang” entered real-time popularity rankings at number one on Netflix and trended high on social media. Just one day after its release, it topped Netflix Korea’s Top 10 series chart, and there is growing interest in how it will perform in the global market.

Netflix’s Mercy for None Review

At first glance, it may seem like a typical revenge story starring So Ji-sub. However, the real charm lies in the psychological warfare between Lee Ju-un, Gu Bong-san, Lee Geum-son, and Cha Young-do, who constantly deceive each other. Unlike other noir works that drag out time with love stories, this series eliminates all unnecessary elements and delivers heavy, desperate action and a fast-paced plot, earning cheers from many fans. It is a Netflix series that delivers catharsis to viewers through clear revenge, without forgiveness or reconciliation.

On set, the chemistry between actors and their improvisations became a hot topic, and actual on-location filming took place at places like Yeouido’s National Assembly Plaza in Seoul. Netflix also opened “Netflix Gwangjang” experience spaces in major cities around the world to interact directly with fans.

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