If you thought the last chapter was intense, Agent Kim Reactivated Episode 4 cranks the tension all the way up. This is the hour where the show finally pulls back the curtain on where Kim came from, why he never breaks, and how far a desperate father will go to save the one person who still matters to him. It is dark, it is emotional, and it leaves you staring at the screen long after the credits roll.
Here is a full, spoiler-heavy breakdown of everything that happens.
A Childhood Built on Pain: The 1997 Flashback
Episode 4 opens in North Korea in 1997, and it is not an easy watch. A cold, calculating recruiter named Yeong Ryung walks into an orphanage looking for children he can shape into weapons. He offers the one thing starving kids cannot refuse — a full stomach.
A boy named Yeong Gyeong steps forward first, tempted by the promise of food. Then we meet a quiet child who wins every fight thrown at him, and finally a smaller boy on the ground who grabs the recruiter’s leg and refuses to be overlooked. That boy gives his name: Kim. In a single scene, the show tells us everything about who Kim is — someone who fights to be seen, even from the bottom.
The training that follows is nothing short of torture. The children are stripped of their names and handed codes. Kim becomes Code 73, and his rival becomes Code 66. Interrogators demand they forget who they are, punishing anyone who dares hold on to their identity. The message is chilling: to survive, you must disappear.
Loyalty, Rivalry, and a Promise That Breaks Your Heart
One of the strongest threads in Agent Kim Reactivated Episode 4 is the bond between Kim and Yeong Gyeong. They are forced to fight, and Kim always wins — but there is no cruelty in him. When Yeong Gyeong refuses to eat, Kim quietly gives him his own food, insisting he is only acting out of pity so Gong can keep his pride. It is a small moment that says a lot about Kim’s humanity.
The brutality never lets up. One night, soldiers move to kill the trainees in their sleep, and Kim wakes to a nightmare — many children slaughtered on the recruiter’s orders. Kim and Gong survive, hardening into the perfect operatives the program wanted.
Then comes the mission that shatters everything. Sent south to eliminate a target, Gong opens fire despite Kim’s warnings — only to discover the “man” is a rigged dummy. The bomb detonates, and Gong dies. The gut-punch lands harder because of an earlier promise: as Gong was once dragged away from his village, he swore he would return. He never got the chance.
Back to the Present: A Father on the Run
The story snaps back to the present, where Kim is a fugitive fighting for his life. In the closing beats of the previous episode, Gang Seong pinned a gun on him, but Kim slips free and, with help, fights back. The confrontation spills into a tense standoff where Sang A and Mr. Lim arrive, weapons drawn, ordering everyone to stand down.
Han Soo demands to know who these people are, and Kim keeps it simple — Sang A is his colleague, and Mr. Lim is another familiar face. Mr. Lim recalls how spotting Gang Seong earlier gave him the thread that led straight to Kim. When Mr. Lim orders Kim to surrender for violating his government contract, Kim refuses with a line that defines the whole series:
He will not surrender until his kidnapped daughter is safe — and once she is, he promises to turn himself in.
Gang Seong seizes the chaos, grabs Mr. Lim’s gun, wounds Sang A, and escapes. Everyone assumes Mr. Lim is dead, but a bulletproof vest saves him. Kim, already shot, bandages himself in the back of the car — quietly enduring pain the way he was trained to.
The Hunt for the Phone and a Villain’s Origin
The trio — Kim, Han Soo, and the newly returned Jin Cheol — chase a lead: a homeless man near the station who took Min Ji’s phone. After some pleading, the man remembers a white BMW pulling up, and a man tossing the phone into a trash bin. That man is Sangman, and the clue cracks the case wide open.
Episode 4 also delivers a knockout origin story for Gold Teeth. Nine years earlier, he was an enforcer crushing protesters during a redevelopment scheme. When his own boss betrays him — pushing him off a rooftop to fake a worker’s accidental fall and clear the way for construction — Gold Teeth survives, pieces together the truth from a hospital news report, and takes bloody revenge.
His path collides with Gang Chan, the show’s true monster. In a scene you will not forget, Gang Chan overpowers Gold Teeth, shoves a scorching-hot potato into his mouth, and declares him his “dog.” Broken and begging, Gold Teeth submits. From that moment, his loyalty is fear, not choice.
Explosions, a Freezer, and a Daughter’s Fight to Live
The action explodes — literally. As the heroes track the target vehicle, Guk Cheol detonates a bomb that sends their car flying. Han Soo buys time with his combat skills so Kim can escape, sacrificing himself to the danger yet again.
Meanwhile, the most harrowing subplot unfolds. Sangman and his men drag Min Ji into a freezer set to minus 30 degrees, killing a security guard who gets in the way. But Min Ji is alive. She claws her way out of the body bag, screaming into the freezing silence where no one can hear her.
The Cliffhanger That Changes Everything
The episode’s final act is a web of betrayal. Gold Teeth calls Gang Chan claiming his daughter Hye Ri killed someone — and sends audio proof. When confronted, Hye Ri admits she killed a girl who bullied her. Gang Chan slaps her, not out of morality, but because she should have let him handle it. His plan is cold: pin Min Ji’s disappearance on Gold Teeth and clean up the mess.
Kim finally reaches the port and finds the white BMW. He corners Sangman, demanding to know where Min Ji is. Gold Teeth, sent to photograph Min Ji as “proof” of her death, gets a call from Gang Chan — and steps outside just long enough for Min Ji to creep toward the freezer door.
Then it happens. As she tries to slip out, Gold Teeth hears her, turns, and sees her face. He realizes she is still alive.
And with that terrifying discovery, Episode 4 cuts to black.
Why This Episode Matters
Agent Kim Reactivated Episode 4 works because it never treats violence as spectacle for its own sake. Every brutal scene serves the story — Kim’s frozen empathy, Gold Teeth’s tragic corruption, Min Ji’s raw will to survive. The flashbacks give the present real weight, turning a spy thriller into a story about identity, guilt, and the impossible things people do for the people they love.
For fans of tightly plotted Korean action dramas, this is the episode that transforms Agent Kim Reactivated from a solid watch into a must-watch. The pieces are on the board, the villains are converging, and Kim is running out of time.
Agent Kim Reactivated Episode 4 Review
My take: Episode 4 is easily one of the strongest hours of the series so far. The 1997 orphanage flashback is genuinely devastating, and it recontextualizes Kim in a way that makes his quiet stubbornness hit harder. Gold Teeth’s backstory adds real depth to a character who could have been a throwaway heavy, and Min Ji’s freezer sequence is edge-of-your-seat television. My only small gripe is that the timeline jumps require your full attention — blink and you may lose the thread. Otherwise, this is confident, emotional, and relentlessly paced storytelling.
Rating: 4.5 / 5 ⭐
