The Dark Truth Unfolds: 'Hyperknife' Episode 5 Reveals Deok-hee's Murderous Past and Se-ok's Burning Rage

The Brutal Truth Behind Myeong-jin's Disappearance
Episode 5 of Disney+'s gripping medical thriller 'Hyperknife' opens with one of the most chilling scenes in the series so far. We finally witness the full truth of what happened between Professor Choi Deok-hee (Seol Kyung-gu) and his friend Myeong-jin Kim. The episode begins with a flashback showing Deok-hee holding a knife against Myeong-jin's throat in his car, allowing him to make one final phone call to his son Ki-tae. This explains the mysterious call that Ki-tae had mentioned to Se-ok in previous episodes.
After the call ends, Deok-hee coldly slashes Myeong-jin's throat and, in a display of his clinical detachment, calmly hands his bleeding friend napkins to staunch the wound. As Myeong-jin staggers out of the car toward a precipice, he ultimately falls to what Deok-hee believes is his death. The professor watches with complete emotional detachment, confirming what we've suspected all along – beneath his sophisticated exterior lies a true psychopath capable of murdering even his closest friends.
Mrs. Ra's Shocking Revelation
The narrative shifts to the present day, where we see Deok-hee confronting Mrs. Ra, his loyal assistant. Between them on the table lies Myeong-jin's ring – the same ring that was discovered in the previous episode. Deok-hee demands an explanation, and Mrs. Ra's confession is unexpected: she had followed Deok-hee that fateful day out of suspicion and managed to save Myeong-jin's life after Deok-hee left the scene.
However, the damage to Myeong-jin's brain was severe, leaving him in a vegetative state. Mrs. Ra reveals she placed him in a nursing home under a false identity to protect both Myeong-jin and, surprisingly, Deok-hee himself. She assures Deok-hee that he need not worry about any consequences, as Myeong-jin had passed away naturally three months ago.
This revelation adds another layer to the complex web of relationships in the series. Mrs. Ra's actions suggest that despite knowing Deok-hee's darkest nature, she remains loyal to him, even going so far as to cover up his attempted murder. Her character emerges as morally ambiguous – neither completely good nor evil, but operating in the gray area that seems to define everyone in this series.

Se-ok's Hunting Expedition and Growing Troubles
Meanwhile, we see Jung Se-ok (Park Eun-bin) embarking on a hunting expedition, where she brings down wild boars with ruthless efficiency. This scene serves as a metaphor for her predatory nature and her need to release tension through violence. Her bodyguard Young-joo senses that something is troubling her, but Se-ok remains characteristically tight-lipped about her concerns.
The pressure on Se-ok intensifies when she's summoned to the police station. Before responding to the summons, she visits Ki-tae at the hospital, where she unexpectedly encounters Deok-hee. In a tense conversation, he reveals a critical piece of information: dog hair was discovered on the murdered nurse's body. Since Se-ok owns Rottweilers, this evidence directly connects her to the crime scene.
Deok-hee offers to help Se-ok evade the police investigation on one condition – that she performs the brain surgery he desperately needs. True to her stubborn nature, Se-ok promptly refuses, maintaining her stance that she will never operate on him despite the mounting legal danger she faces.
The Devastating Fire
The episode takes a shocking turn when Se-ok's house unexpectedly catches fire, resulting in the tragic death of her beloved Rottweilers. This devastating loss affects Se-ok deeply, as the dogs were among the few living beings she seemed to genuinely care for. The timing of the fire is suspicious, occurring just as the police investigation is closing in on Se-ok and the dog hair evidence could potentially lead to her arrest.
In the aftermath of the fire, Se-ok calls Deok-hee, directly accusing him of setting the fire. Her accusation is twofold: she believes he did it not primarily to protect her by destroying evidence, but to manipulate her into feeling indebted to him. In her view, Deok-hee is attempting to break her spirit so that she will ultimately agree to operate on him.
This scene showcases the deep understanding these two characters have of each other. Se-ok immediately sees through what would appear to others as a protective act, recognizing the manipulative intent behind it. Their relationship continues to evolve as a complex dance of power, manipulation, and mutual understanding that transcends normal human connections.

The Psychological Chess Game Intensifies
Episode 5 further develops the psychological chess game between Se-ok and Deok-hee. Despite their mutual hatred, there exists an undeniable bond between them. Deok-hee insists that he is doing everything in his power to protect Se-ok from the police investigation, even as she refuses to help save his life through surgery.
This dynamic illustrates the paradoxical nature of their relationship – they are simultaneously each other's greatest enemies and the only people who truly understand one another. Deok-hee's willingness to protect Se-ok despite her refusal to operate on him suggests that his feelings toward her are more complex than simple manipulation. Similarly, Se-ok's continued engagement with Deok-hee, rather than simply avoiding him entirely, indicates that she remains drawn to their toxic connection.
The episode excels in portraying the psychological complexity of these characters. Both are brilliant minds with psychopathic tendencies, yet they express these tendencies differently. Their mutual fascination and repulsion create a compelling narrative tension that drives the series forward.
Critical Acclaim and Viewer Response
Episode 5 of 'Hyperknife' has created significant buzz among viewers and critics alike. The medical thriller continues to captivate audiences with its dark storyline and psychological depth. Park Eun-bin's transformation from her typically warm roles to the cold, calculating Se-ok continues to draw praise, with many noting her ability to convey complex emotions through subtle facial expressions and body language.
Seol Kyung-gu's portrayal of Deok-hee also receives acclaim for its nuanced depiction of a character who maintains a veneer of sophistication while harboring murderous impulses. The chemistry between the two leads creates a palpable tension that keeps viewers engaged throughout each episode.
The series' visual style, with its eerie tone and sharp transitions, effectively heightens the psychological tension. Scenes often linger uncomfortably long on characters' faces, making their emotions feel raw and real. This directorial choice contributes to the unsettling atmosphere that has become the show's trademark.
As 'Hyperknife' moves into its final episodes, viewers are left wondering: Will Se-ok eventually agree to operate on Deok-hee? Will she face consequences for her crimes? And perhaps most intriguingly, can these two brilliant but damaged individuals find a way to save each other, or are they destined to bring about mutual destruction?