Episode 5 of The WONDERfools opens with pure confusion and disbelief as Chae-ni suddenly comes back to life right in front of Un-jeong. After everything that happened, he can barely process what he’s seeing before collapsing in her arms beneath the glowing Northern Lights. While Un-jeong loses consciousness, Chae-ni rushes back to the junkyard and discovers Ro-bin unconscious nearby, proving just how disastrous the entire confrontation truly was.
Elsewhere, tensions rise between Ho-ran and Pal-ho after the failed attack. Ho-ran openly mocks him for getting injured by Un-jeong, especially after noticing that the strange defect spreading through his arm is becoming worse. According to her, the damage is slowly making his arm unusable. Before their argument escalates further, Ju-ran intervenes and calms the situation. During the exchange, Ho-ran briefly reflects on her childhood connection with Un-jeong, hinting that her complicated feelings toward him still remain unresolved.
Back at home, Chae-ni and Ro-bin bring the unconscious Un-jeong to his apartment and help him rest. While changing his clothes, they notice countless scars and wounds covering his body, quietly revealing how much pain he has endured alone.
The following day, Gyeon-un and Ro-bin head out to buy medicine for Un-jeong. Their conversation quickly turns serious as they discuss Pal-ho’s mission to hunt down and eliminate “defective variants.” Realizing they may become future targets themselves, the two begin worrying about how they can possibly survive against enemies far stronger than them.
Meanwhile, Jun-mo becomes increasingly suspicious about everything happening in Haeseong. After hearing details about the junkyard incident from Jeon-bok, he grows frustrated that Chae-ni refuses to explain the truth. Determined to uncover things himself, he secretly investigates the junkyard and discovers bloodstains left behind from the battle, making him even more convinced that something dangerous is being hidden from him.
At the same time, Chae-ni stays close to Un-jeong while he struggles through terrifying nightmares. During his sleep, he cries out for his mother, and Chae-ni gently comforts him, showing a softer side to their growing relationship.
Later that night, Jeon-bok notices Chae-ni sneaking out of the house. Although she tries stopping her, Chae-ni ignores the warning and returns to Un-jeong’s apartment. By the time Un-jeong wakes up, he finds medicine and supplies carefully left behind for him by Chae-ni.
The next morning, Chae-ni, Gyeon-un, and Ro-bin wait outside City Hall for Un-jeong. The moment he arrives, he immediately attempts to avoid them, but Chae-ni stubbornly refuses to let him leave alone. Clinging to him, she insists that the four of them should work together as a proper team from now on. Watching from afar, Ho-ran becomes visibly jealous seeing Un-jeong growing closer to Chae-ni.
Eventually, Un-jeong takes the trio back to the hidden training room where he previously helped them awaken their abilities. Once again, he pushes them to control their powers more effectively. However, their training session is interrupted when Ho-ran suddenly appears and traps Chae-ni, Gyeon-un, and Ro-bin inside terrifying hallucinations. While distracting the others, she confronts Un-jeong directly about the mysterious Child of Eternity.
Despite Ho-ran’s pressure, Un-jeong refuses to cooperate with her. He manages to break her influence over the others, forcing Ho-ran to retreat in frustration.
That night, Un-jeong finally reveals the truth about the Child of Eternity to Chae-ni. According to him, the child possessed an immortal heart and could never truly die. He then shocks Chae-ni by suggesting she may now carry the same power. Un-jeong asks whether she underwent a heart transplant as a child, but Chae-ni dismisses the idea entirely. Still, Un-jeong insists that Jeon-bok was connected to the experiments conducted at Hawondo Lab.
Unable to ignore his words, Chae-ni returns home and confronts Jeon-bok directly about the surgery. Meanwhile, Un-jeong remains haunted by thoughts of the Child of Eternity and what it truly means.
Jeon-bok finally confesses the horrifying truth. After the fire at Hawondo Lab, the Child of Eternity suffered irreversible brain damage, though the child’s heart continued beating. Eventually, the child died, and the heart was transplanted into Chae-ni, who had been terminally ill at the time.
Shocked by the revelation, Chae-ni searches through old newspaper articles and archived records connected to Hawondo Lab. As she learns more about the orphan children who were experimented on, she becomes devastated by the cruelty behind everything.
Later, Un-jeong quietly follows Chae-ni after spotting her outside alone. Overwhelmed with guilt, Chae-ni blames herself for the tragedies currently unfolding around them. Elsewhere, Jeon-bok privately discusses the junkyard incident with Jun-mo, further suggesting that the truth is slowly closing in on everyone.
The next day, Un-jeong worries after realizing Chae-ni has disappeared again. Later that evening, she finally visits his apartment, where he awkwardly offers her food. The two spend time together walking to a convenience store, and during their conversation, Chae-ni opens up about her transplant. Un-jeong reassures her that none of the terrible events were her fault and tells her to stop carrying guilt for things beyond her control.
Meanwhile, Ro-bin delivers food from Jeon-bok to Chae-ni, leading to one of the episode’s most emotional moments. Chae-ni breaks down in tears while Jeon-bok quietly cries on her walk home. Although Chae-ni eventually returns home, she still refuses to forgive her grandmother. Instead, she tells Jeon-bok that both of them will spend the rest of their lives repenting for the sins connected to Hawondo Lab.
Not long afterward, Chae-ni and Ro-bin suddenly move into Un-jeong’s apartment without permission, creating some lighter and more chaotic moments. The following day, Un-jeong resumes their training and experiments with ways to strengthen Chae-ni’s powers. Realizing her abilities react to her heart rate, he gives her caffeine to stimulate her body, successfully helping her teleport between locations.
At one point, Chae-ni grabs Un-jeong’s hand and accidentally teleports both of them to a beach. Although she still lacks control, the moment further strengthens the emotional bond growing between them.
Later, Chae-ni secretly prepares a birthday surprise for Un-jeong with help from Ro-bin and Gyeon-un. While buying a cake that evening, she unexpectedly runs into Un-jeong, and the two spend more quiet time together. During their conversation, Un-jeong admits he does not even know whether he truly has a mother.
The emotional atmosphere continues building as Chae-ni promises she will always stay by his side.
Then the episode suddenly delivers its biggest shock.
Without warning, Un-jeong injects Chae-ni with a drug and watches as she loses consciousness. Dr Ha’s followers immediately abduct her, revealing that Un-jeong has secretly been working with them all along.
In the final moments of the episode, Un-jeong explains Chae-ni’s powers to Dr Ha, including the connection between her abilities and her heart rate. However, he intentionally avoids mentioning the caffeine discovery, subtly suggesting that his loyalty may not be completely genuine. The episode ends with Chae-ni being taken away, leaving everyone’s trust shattered.
Episode 5 Review
This episode ended with a betrayal that genuinely caught me off guard. Up until now, Un-jeong had slowly been positioned as someone protective of Chae-ni, so seeing him suddenly hand her over to Dr Ha completely changes the emotional dynamic of the series.
What makes the twist even more confusing is that Un-jeong previously seemed to be investigating the Church of Eternal Salvation independently. If he was truly working with Dr Ha from the beginning, then some of his earlier actions do not fully line up yet. It feels like the drama is intentionally hiding part of his true motivation.
The emotional storyline surrounding Chae-ni’s heart transplant also feels a little uneven. Her guilt over receiving the Child of Eternity’s heart does not entirely make sense logically because she was just a child who underwent surgery to survive. The responsibility clearly belongs to the people behind the experiments, not her.
Still, despite some messy logic, Episode 5 does a good job raising the stakes emotionally. The mystery surrounding Hawondo Lab continues getting darker, and the final betrayal creates enough tension to make the next episode hard to resist. The biggest question now is whether Un-jeong is truly betraying Chae-ni, or secretly trying to protect her from something even worse.
