The Ending Of The Worst Of Evil Explained

Arriving on Hulu at the end of 2023 is "The Worst of Evil," a gritty South Korean crime drama that turned heads with an engrossing story surrounding an undercover drug sting. The series, written by Jang Min-suk and directed by Han Dong-wook, stars Ji Chang-wook as a patrol officer who takes on a new identity as a small-time gangster to ferret out an illegal drug-smuggling ring.

Deep undercover in one of the nation's most dangerous emerging gangs, Officer Park Jun-mo (Ji) becomes Kwon Seung-ho and infiltrates Gangnam Union, a notorious gang run by DJ-turned-kingpin Jung Ki-cheol ("Squid Game" star Wi Han-joon). But the stakes ratchet up when Jun-mo's wife, Yoo Eui-jeong (Im She-mi), is drawn into the investigation and her life is put at risk. To take down Ki-cheol, Jun-mo will not only have to pose as a criminal himself but become part of an escalating gang war between rivals inside and outside of Korea, all while attempting to gather hard evidence of an international drug operation.

A taut, gripping thriller full of shocking twists in nearly every episode, "The Worst of Evil" shows how the toughest detective work can destroy the lawmen as much as the criminals they hunt. In its stirring conclusion, lives hang in the balance, but unraveling all the threads may take a little work. This is the ending of "The Worst of Evil" explained.

"The Worst of Evil" is no ordinary crime drama. A complex tale of betrayal, it involves players from around the world, each with their own goals and loyalties. While the police in Seoul, led by Jo Chang-sik (Lee Jung-hun) and Detective Seok Do-hyung (Ji Seung-hyun), send Park Jun-mo undercover under the alias of Kwon Seung-ho, they're not the only group lawmen after Gangnam Union. Local Gangnam police officer Hwang Min-goo (Yoon Kyung-ho) also becomes obsessed with nailing the gang's leader, Jung Ki-cheol, and his investigation only gets in the way of the undercover operation.

At the same time, Gangnam Union is dealing with fights with multiple rival gangs, first from Jang Kyeong-cheol (Jeong Man-sik), and later, the Jaegon Group, another "company" of organized criminals in the region. The various gangs fight for control of the city streets and its burgeoning drug trade — thanks to the fresh import of a new drug called Gangnam Crystal. But the import of that drug means Gangnam Union is making international deals with both the Japanese crime syndicate the Yakuza — under the command of Kanemeto (Ki Guk-seo) — and drug suppliers in China who use the Koreans the funnel their product into Japan. At the same time, Ki-cheol must stave off attempts by his superiors to remove him as head of Gangnam Union, while also fighting off a coup within his ranks.

When Park Jun-mo is sent undercover into the Gangnam Union, he poses as Kwon Seung-ho, the unseen cousin of their leader Jung Ki-cheol's right-hand man, who was killed in a fight with another gang. This identity helps earn Ki-cheol's trust, and in time, Jun-mo works his way up through the ranks by showing unfailing loyalty to the organization. Eventually, he becomes Ki-cheol's driver, bodyguard, and confidante. But when Jun-mo's wife learns of his dangerous assignment — and that Ki-cheol is her former high school boyfriend who had left town when he was young — she insists on becoming part of the investigation by rekindling her romance with the gang leader.

At the same time, Ki-cheol's lieutenant and longtime friend, Choi Jeong-bae (Lim Seong-jae), becomes suspicious of Jun-mo. He also objects when Ki-cheol begins dating Eui-jeong — a police officer — leading to his violent expulsion from Gangham Union. All the while, Jun-mo is attempting to press Ki-cheol toward a massive impending drug deal with their Chinese suppliers, whose liaison Lee Hae-ryeon (Kim Hyung-seo) has become smitten with him, giving him added leverage. When the deal nearly falls apart, though, Jun-mo and Eui-jeong must use their new romances to push Ki-cheol and Hae-ryeon into the trade or risk the entire investigation going up in smoke. When Ki-cheol too becomes suspicious, he sends his most dangerous henchman, the knife-wielding Chief Seo (Lee Shin-ki) to get to the truth.

Despite steps to throw Jung Ki-cheol and Gangnam Union off the scent of Jun-mo, some within the group decide to dig deeper, and Seo finally gets proof that Kwon Seung-ho is really an undercover cop. And when Seo sets a trap for him, it leads to the murder of Detective Do-hyung, pushing Jun-mo over the edge. Though he's able to stop Seo from exposing him to Ki-cheol, he can't prevent former Gangnam Union lieutenant Choi Jeong-bae from exacting revenge and taking control of the gang. Pushing Ki-cheol aside, Jeong-bae takes over the group's big drug deal and completes the trade with their Chinese benefactors — forcing cops to arrest Jeong-bae instead of Ki-cheol.

Jun-mo, meanwhile, reveals his true identity to Ki-cheol, but in the chaos of the drug bust, the gang leader makes his escape. In the aftermath, Ki-cheol tracks down Jun-mo and Eui-jeong and threatens to kill them both for their betrayals and lies — Jun-mo for his false friendship and Eui-jeong for using his love for her to manipulate him. But in a shocking confrontation, Ki-cheol turns the gun on himself, and in a fateful final decision, Jun-mo shoots him in the chest rather than let the gangster take his life.

As the dust settles, Park Jun-mo and Yoo Eui-jeong return to their jobs but realize too late that the investigation has taken too large a toll on them. While Jun-mo gets his promised promotion, their relationship has been strained too far, and we see Jun-mo removing his wedding ring and placing it on the grave of Ki-cheol, his old nemesis and one-time friend.

With so many emotional moments at the end of "The Worst of Evil," there's a lot that can be read from the jaw-dropping conclusion, but not all of it is as cut-and-dry as it may seem. For starters, Ki-cheol's escape amid the drug deal was no lucky maneuver: Jun-mo intentionally allowed him to get away, giving the appearance of a bust by handcuffing him to the steering wheel of their car, but purposefully leaving him the keys in the ignition. It would seem that the brotherly relationship forged between them during the undercover operation may have been more real than Jun-mo would like his superiors to believe.

Still, some may question why Jun-mo shot Ki-cheol when he was ready to end his life in that final scene — after all, the result was the same. But with his wife Eui-jeong with them in that moment, Jun-mo may have been attempting to spare her the guilt of his suicide by being the one who pulled the trigger. The irony of this, of course, is that killing Ki-cheol may have been the final nail in the coffin of their relationship. During their investigation, Jeong's romantic relationship with Ki-cheol — though a ruse — stirred up powerful emotions in her, and she began to push the gangster into leaving a life of crime behind, undermining the entire investigation. 

So when Jun-mo murdered the man she once called a lover — whom she still felt was deserving of a second chance — it pushed her further away from him, and the two couldn't reconcile their differences.

When Jun-mo is first offered the assignment to go undercover in Gangnam Union he initially refuses. It's a dangerous operation, and he doesn't like the idea of becoming a gangster himself and taking part in crimes just to stop Jung Ki-cheol. But the assignment also offers him the opportunity to advance in his career, as he's been held in the lower ranks of the police force for far too long. He accepts the assignment, but in exchange for going undercover, he negotiates a major promotion in rank. Because Jun-mo grew up in poverty, this is finally his chance to get the respect he feels he's long deserved.

In truth, though, the criminal kingpin Ki-cheol isn't that much different than Jun-mo. He too grew up in poverty, with an abusive father, and has for too long been looked down on by the people in his hometown. So when as a local DJ he's offered the chance to become rich, he jumps headlong into a world of crime. Through the Gangnam Union, Ki-cheol finally becomes wealthy, powerful, and respected, but to get there, he's lost touch with many of his old friends. He's alienated even those closest to him while being obsessed with his success. Similarly, Jun-mo too loses sight of his marriage in his determination to take down Ki-cheol and secure a raise in rank. Jun-mo and Ki-cheol are really two sides of the same coin, showing the divergent paths of two similar people.

At the beginning of "The Worst of Evil," Park Jun-mo and Yoo Eui-jeong are in a loving marriage, with the only problem seemingly being Jun-mo's frustration over his low rank on the police force. By the end of the series, however, their marriage has crumbled, and Jun-mo walks away from his wedding ring after getting his big promotion, with Eui-jeong on the outside looking in. So what led to their deep bond breaking? 

The first cracks begin to form after Eui-jeong discovers that Jun-mo is undercover, and she's livid that he's even accepted such a dangerous assignment. She refuses to let his police comrades put him in danger alone, though, and quickly becomes a part of the active investigation. Learning that their target is an ex-boyfriend, Eui-jeong initiates a relationship with Ki-cheol while Jun-mo — in his alias as Kwon Seung-ho — claims to have been friends with her as a young child. But working together under false pretenses creates new problems, as Jun-mo is forced to watch her become romantically involved with Ki-cheol and isn't happy to discover that they had once been lovers.

Eui-jeong, meanwhile, is uncertain of Jun-mo's romance with Lee Hae-ryeon, and the trust between them begins to break down. The real problems surface when an attack on Gangnam Union forces Jun-mo to become a killer in front of Eui-jeong. She is disturbed by his potential for violence, a side of him Eui-jeong never knew, and finally, Jun-mo's murder of Ki-cheol pushes her away for good.

One of the most striking elements of "The Worst of Evil" isn't its brutal violence — of which there's plenty — it's the staggering number of backstabbing and betrayals. And it starts almost immediately. Early on in the series, Ki-cheol's boss allows rival Jang Kyung-chul to challenge him for control of Gangnam, only for Ki-cheol to fend off multiple takeover attempts and firmly establish himself as the region's top dog. But that's not the last time he'd have to deal with betrayal.

Heading into the finale, both the Yakuza in Japan and their drug suppliers in China are ready to betray Gangnam Union. Shockingly, a backstabbing Yakuza underboss kills the organization's leader and takes over the deal. But just as that deal is about to go down, Choi Jeong-bae returns to betray Ki-cheol — and yet that's not the double cross that deals the worst blow to Jun-mo and his investigation.

Instead, it's Officer Hwang Min-goo, who had been consumed with rage over finding evidence on Ki-cheol, completely unaware of Jun-mo's undercover operation. But it isn't just his meddling in the case that threatens to blow Jun-mo's cover — the end of "The Worst of Evil" reveals Min-goo is in cahoots with Jeong-bae and helps expose Jun-mo's real identity. Min-goo gets his comeuppance, though, when Lee Hae-ryeon murders him after he reveals that her lover Kwon Seung-ho is actually an undercover cop.

It's actually something of a major plot twist when Jung Ki-cheol first meets Jung-Mo's wife. An accidental meeting that almost exposes Jun-mo's cover, it stuns him to learn that his wife was once the high school sweetheart of the very man he's trying to put away for drug smuggling. Throughout the season, repeated flashbacks show more about their past relationship, and how Ki-cheol had promised to one day marry Eui-Jeong after becoming a successful business owner. Reconnecting years later, Ki-cheol now has everything he ever dreamed of, and he attempts to fulfill that promise.

Eui-Jeong then begins dating Ki-cheol as part of the police investigation. But as the two become reacquainted, it becomes clear that she still may harbor some romantic feelings for the leader of Gangnam's most notorious gang. As a police officer, she couldn't ever actually be involved with him, but the resurfaced emotions create problems, and instead of attempting to put him behind bars, Eui-jeong tries to push Ki-cheol into going straight and leaving a life of crime.

Jun-mo, meanwhile, is forced to act out a romance with Lee Hae-ryeon. And in what might be the most unexpected romantic twist, Hae-ryeon actually helps protect Jun-mo even after she discovers that he's an undercover officer, proving that her love for him is very real.

The big hallway fight scene, that saw Park Jun-mo soaked in his enemies' blood, didn't just disappoint actor Im She-Mi. Even Ji Chang-wook, who plays Jun-mo, wasn't entirely thrilled with the sequence, and he gets all of the best moves. But for Chang-wook, it wasn't disappointment with the script or even the final edit, because he was truly impressed with how it all turned out. Instead, it was the audience's reaction to the episode that left him irked.

"The scene of fighting in the hallway of the office was filmed with one take, and I thought people would like this scene," he said in an interview with Daum (translated by Dexerto). "But it was a pity that the kissing scene became more a hot topic than this," he said. That kiss, between Jun-mo and Lee Hae-ryeon, was what stunned the audience most.

"[The hallway fight was] an act of trying to save [Eui-jeong], but I wanted to draw the evil deeds I did in it in a desperate and scary way," he said. Chang-wook said he personally requested more blood be used in the scene, but despite all his attempts to shock viewers, Jun-mo's violent turn was almost entirely overshadowed by his kiss with Hae-ryeon.

"The Worst of Evil" is the story of a husband and wife who must compromise their marriage to go undercover and stop drug kingpin Jung Ki-cheol. Jun-mo leads the investigation from the inside, and he sees a fair amount of action and gets involved in some violent encounters, one of which leaves him close to death. His wife, Eui-jeong, plays more of a passive role, psychologically manipulating Ki-cheol — but actor Im She-mi, who plays Eui-jeong, says that she actually filmed her own fight scene that got cut from the ending. 

"I had one action scene," she told Screen Rant. According to Im, the epic hallway fight between Gangnam Union and a rival gang, which occurs while Eui-Jeong is visiting Ki-cheol, originally saw her taking part in the fighting. "It was edited out in the end, so Eui-jeong was portrayed as being protected by the two men. But it did not disrupt the overall flow of the story, so it turned out well." Though Im approves of the final cut, she seems disappointed that they chose to downplay Eui-jeong's strength and ferocity. "I do hope to have the opportunity to do a proper action project with a female-led story," she said.

With Gangnam Union busted and Jung Ki-cheol dead at the end of "The Worst of Evil," the story would seem to be over, as most of the loose ends are tied up neatly. But the show's success means we can't completely count out a second season, and with the series being as much about the relationship between Jun-mo and Eui-jeong as it is about an undercover criminal investigation, there's still plenty to explore in a possible Season 2. Could the two detectives be brought back together on a new case, forcing them to confront their past and what drove them apart?

Considering the show's 1990s setting, too, there's even the potential for a second season to take place years, or even a decade later. This could allow the opportunity to explore Jun-mo and Eui-jeong's relationship from a new perspective and show us a different side of the characters while allowing the opportunity for jailed gangsters like Choi Jeong-bae and Seo to return after spending time behind bars. 

But even if it takes place in the immediate aftermath of Season 1, following Jun-mo's career on a new case may be too good an opportunity to pass up. Whether that means Jun-mo going undercover again or using his experiences to oversee a new sting as a commander, we find it hard to believe that adamant Hulu viewers won't want to see more of the story.