Following the phenomenal success of “Mantis” earlier this year, tvN’s prequel series “Mantis: Original Sin” arrived with sky-high expectations. I’m thrilled to report that this 10-episode limited series not only meets those expectations but transcends them, offering a haunting exploration of how monsters are made.
A Bold Narrative Choice
Rather than simply continuing the original storyline, “Mantis: Original Sin” takes us back 20 years to focus on the events leading up to the murder that shaped Park Ji-won’s life. The series centers on Ji-won’s mother, the brilliant but troubled forensic pathologist Yoon Hee-jin (played by the incomparable Bae Doona).
Set in 2005, we find Hee-jin investigating a series of seemingly unrelated deaths that only she believes are connected. Her obsession with finding patterns others cannot see strains her relationships, particularly with her young daughter Ji-won (child actress Kim Yu-na in a remarkably nuanced performance). As Hee-jin unravels the conspiracy, she comes face-to-face with forces that will eventually lead to her demise.
Performances That Captivate
Bae Doona delivers what might be the finest work of her already illustrious career. Her Hee-jin is intense and single-minded, yet deeply vulnerable. Doona masterfully conveys Hee-jin’s brilliant mind through subtle physical choices – the way she tilts her head when analyzing evidence or the slight tremor in her hands when she’s onto something no one else can see.
Jo Jung-suk is equally compelling as Detective Choi Min-ho, Hee-jin’s reluctant ally who harbors his own secrets. Their relationship forms the emotional core of the series – two broken people finding understanding in each other while knowing they can never truly be saved.
The supporting cast shines as well, particularly Yoo Jae-myung as the enigmatic hospital director whose benevolent façade hides something far more sinister. His quiet menace creates tension in even the most innocent interactions.
A Visual Feast
Director Kim Hee-won (known for “Vincenzo”) crafts a visual aesthetic that complements the original series while establishing its own identity. Where “Mantis” was cool and clinical, “Original Sin” embraces a warmer yet more ominous palette – golden hour shots that feel like the last light before darkness falls.
The 2005 setting is rendered with meticulous attention to detail without resorting to nostalgic clichés. Seoul appears as a city in transition – racing toward modernity while still haunted by its past, perfectly mirroring Hee-jin’s internal struggle.
Narrative Complexity
Writer Lee Soo-yeon has constructed a narrative that functions brilliantly as both standalone storytelling and enrichment of the original series. Each episode peels back another layer of the conspiracy Hee-jin uncovers, while simultaneously deepening our understanding of characters we thought we knew from “Mantis.”
The pacing is deliberate but never sluggish, allowing moments of quiet character development to breathe between intensely suspenseful sequences. The writers trust their audience’s intelligence, planting subtle clues that reward attentive viewing.
What elevates “Original Sin” beyond typical prequels is how it complicates our understanding of the original series without undermining it. Revelations about Hee-jin’s research and her final discoveries cast the events of “Mantis” in an entirely new light, encouraging viewers to revisit the original with fresh eyes.
Final Thoughts
“Mantis: Original Sin” accomplishes the rare feat of enhancing its predecessor while standing firmly on its own merits. It’s a meditation on how our attempts to protect those we love can sometimes cause the greatest harm, and how truth, once buried, finds ways to surface through the most unexpected channels.
The series’ final episode delivers an emotional gut-punch that resonates even more powerfully for those familiar with where the story ultimately leads. The circular nature of tragedy across generations becomes heartbreakingly clear.
For fans of the original “Mantis,” this prequel is essential viewing that enriches the mythology. For newcomers, it serves as a perfect entry point into this darkly compelling universe. Either way, “Mantis: Original Sin” stands as one of 2025’s most thoughtfully crafted K-dramas.
Have you watched both “Mantis” series? Which revelation surprised you most? Share your thoughts in the comments below!
Where To Watch:
- Netflix
