The Shocking Truth Revealed: 'Hyperknife' Episodes 3 & 4 Prove Both Master and Student Are Psychopaths
The Master and Student: Two Sides of the Same Coin
Episodes 3 and 4 of Disney+'s gripping medical thriller 'Hyperknife' finally answer the burning question that's been haunting viewers since the beginning: why did Professor Choi Deok-hee (Seol Kyung-gu) once tell Jung Se-ok (Park Eun-bin) that they were alike? The shocking truth is revealed - teacher and student are indeed cut from the same cloth. Both are brilliant medical minds with psychopathic tendencies, though they express them differently. Deok-hee is a refined, calculated killer who maintains a veneer of sophistication, while Se-ok is a raw, unpolished psychopath who acts more impulsively.
This duality creates a fascinating psychological dynamic between the two characters. While they have vastly different personalities - Deok-hee being meticulous and controlled, Se-ok being free-spirited and unrestrained - their fundamental moral compasses (or lack thereof) are identical. Both are willing to kill to get what they want, and both view human life as disposable when it interferes with their desires. The revelation that Deok-hee is just as morally corrupt as Se-ok recontextualizes their entire relationship and explains why he was able to recognize her darkness from the beginning.
The Failed Surgery Sabotage
A pivotal flashback in episode 3 shows Deok-hee's friend from Los Angeles, Kim Myung-jin, requiring brain surgery. Surprisingly, Deok-hee calls for Ha Woo-young instead of Se-ok to assist with the operation, breaking from his usual preference. Se-ok, sensing something amiss, forces her way into the operating room and deliberately stabs Deok-hee's hand with a scalpel to take over the surgery herself.
What Se-ok realizes during this operation is chilling - Deok-hee was intentionally planning to botch his friend's surgery. This revelation is our first concrete hint that Deok-hee harbors the same dark impulses as Se-ok. Despite Deok-hee's attempts to sabotage the procedure by having the less skilled Woo-young assist, Se-ok ensures the surgery is successful, unknowingly thwarting Deok-hee's murderous plan.
The scene brilliantly foreshadows the central conflict of the series: two brilliant minds with similar darkness constantly trying to outmaneuver each other. Se-ok's intuitive understanding of Deok-hee's intentions also highlights their psychological connection - she can read his motives because they think alike, despite their outward differences.
The Buried Secrets
Episode 3 continues directly from the cliffhanger of episode 2, with Deok-hee discovering Se-ok burying the body of a sex offender she has murdered. What's striking is Deok-hee's complete lack of surprise or horror at finding his former student committing such a heinous act. Instead, he calmly tells her she should start a new life in Boston rather than continuing down this path.
When Se-ok refuses Deok-hee's request to perform surgery on him, he retaliates by reporting her illegal pharmacy and Han Hyun-ho's hospital to the Ministry of Health and Welfare, resulting in both establishments being shut down. This vindictive move reveals Deok-hee's willingness to destroy others when they don't comply with his wishes.
The discovery of the nurse's body that Se-ok had previously murdered creates another tense moment when both Se-ok and Deok-hee encounter each other at the crime scene. Rather than turning her in, Deok-hee tells Se-ok to leave quickly, further cementing the complex bond between them - one built on mutual understanding of each other's darkness.
The Revenge and the Award
Furious at Deok-hee for shutting down her pharmacy, Se-ok seeks revenge in a particularly calculated way. Learning that Deok-hee is about to receive the prestigious Ichida Award for the tenth consecutive year, she travels to Busan where she encounters an opportunity - Ichida's son needs a complex brain surgery.
Se-ok makes a deal - she'll perform the surgery successfully on the condition that the Ichida Award goes to someone other than Deok-hee. After flying to Japan and successfully completing the operation, the award indeed goes to another doctor, breaking Deok-hee's winning streak. Se-ok feels triumphant, only to later discover that Deok-hee had already spoken with Ichida and recommended Se-ok for the surgery, once again demonstrating that he remains one step ahead of her.
This chess match between the two characters highlights their intellectual brilliance and their shared tendency to use others as pawns in their personal games. The difference lies in their execution - Deok-hee's moves are always more sophisticated and forward-thinking, while Se-ok, though brilliant, still lacks his level of calculation and foresight.
The Missing Friend Mystery
The most shocking revelation comes when Se-ok meets Kim Myung-jin's son, Ki-tae, who reveals his father mysteriously disappeared after a final phone call. Se-ok immediately suspects Deok-hee murdered his friend rather than this being a simple case of abandonment.
Se-ok and Ki-tae visit the mental hospital where Myung-jin was last seen and find an informant who claims to have information. During a confrontation, Ki-tae notices his father's ring on the informant's finger, leading to a physical altercation that sends both men over a cliff. The informant dies while Ki-tae is left unconscious in critical condition.
Se-ok confronts Deok-hee with the ring, demanding to know why he killed his friend. Though Deok-hee doesn't respond, the episode ends with a shocking scene - Deok-hee returning home and unveiling Myung-jin's Rolls-Royce that he had kept hidden. A flashback reveals Deok-hee holding a knife to Myung-jin's throat during his last phone call with his son, confirming Se-ok's suspicions were correct all along.
The Perfect Crime vs. The Imperfect Criminal
Episode 4 delves deeper into the past relationship between Se-ok and Deok-hee, revealing that this isn't the first time Deok-hee has covered up Se-ok's crimes. In a flashback, Deok-hee and Woo-young visit Se-ok's home when she fails to show up for an important surgery. They find her with signs of assault on her face, but she refuses to explain.
While Se-ok secretly calls Woo-young for help, Deok-hee discovers a corpse in her storage room. Se-ok claims she killed the man in self-defense when he tried to attack her. Rather than reporting her, Deok-hee simply asks if she can handle disposing of the body alone, marking the first time he turned a blind eye to her murderous tendencies.
This scene is pivotal as it shows Se-ok feeling a moment of joy, believing Deok-hee truly understands her. The parallel between their methods becomes clear - while Se-ok is reckless and leaves evidence, Deok-hee is methodical and commits perfect crimes. When a detective begins suspecting Se-ok of the nurse's murder due to Rottweiler dog hair found at the scene, Deok-hee drugs the detective, demonstrating his willingness to eliminate threats to protect himself, not Se-ok.
The Psychological Duality
What makes 'Hyperknife' so compelling in episodes 3 and 4 is the exploration of psychological duality between the two main characters. Despite their different personalities and approaches, Deok-hee and Se-ok share the same fundamental darkness - a willingness to kill without remorse to achieve their goals.
The series brilliantly portrays how Deok-hee maintains a façade of moral superiority while harboring the same murderous tendencies as Se-ok. His pristine appearance and reputation as a respected neurosurgeon contrast sharply with his actions, making his character perhaps even more disturbing than Se-ok's more obvious psychopathy.
As these episodes conclude, it becomes clear that the central conflict of the series isn't simply about a mentor and student at odds, but about two similar minds engaged in a dangerous game of chess where human lives are merely pawns. The revelation that Deok-hee murdered his friend Myung-jin confirms that he is just as capable of cold-blooded killing as Se-ok, setting the stage for an even more intense battle of wits in the remaining episodes.