What would happen if someone didn’t just steal your money—but stole your name, identity and entire life?
That disturbing question is at the center of Mousetrap, Netflix’s new Korean mystery thriller starring Ryu Jun-yeol, Sul Kyung-gu and Lee Kyoo-hyung.
Released on August 28, 2026, the 10-episode limited series combines identity theft, psychological suspense and a uniquely Korean piece of folklore about a mysterious rat that can take a person’s place.
If you’re wondering whether Mousetrap is worth watching, here’s everything you need to know about its cast, episodes, Netflix release, webtoon source and unusual Korean folklore connection.
What Is Mousetrap About?
Mousetrap follows Je Moon-jae, a reclusive novelist who has isolated himself from society.
His strange nightmare begins when ordinary parts of his identity suddenly stop working.
His fingerprint no longer unlocks his phone.
His passwords fail.
His money disappears.
Eventually, Moon-jae realizes that someone hasn’t simply hacked his accounts.
Someone appears to have taken over his entire identity.
The mysterious figure responsible calls himself “The Rat.”
With his name, money and identity slipping away, Moon-jae is forced out of isolation and into a dangerous search for the person who seems to know his life better than he does.
Mousetrap Cast
Ryu Jun-yeol as Je Moon-jae
Ryu Jun-yeol plays Je Moon-jae, a genius novelist who lives in isolation.
After his identity is stolen, Moon-jae suddenly finds himself unable to prove that he is actually the person he claims to be.
The role gives Ryu an especially interesting acting challenge because the story revolves around the difference between a real person and someone who has taken over that person’s identity.
For viewers who know Ryu Jun-yeol from The 8 Show or Revelations, Mousetrap offers another dark psychological role.
Sul Kyung-gu as Noja
Sul Kyung-gu plays Noja, a ruthless loan shark.
At first, Noja appears to be another threat in Moon-jae’s rapidly collapsing life.
But circumstances force the two men into an unlikely alliance.
Noja wants his missing money back, while Moon-jae desperately wants his identity and life back.
Their uneasy partnership becomes one of the most interesting relationships in the series.
Lee Kyoo-hyung as Sun-yong
Lee Kyoo-hyung plays Sun-yong, a detective investigating the mysterious case surrounding The Rat.
As the investigation progresses, he becomes increasingly connected to the strange web of identities and hidden truths surrounding Moon-jae.
The three characters approach the mystery from very different positions, creating a chase in which it becomes increasingly difficult to know who is telling the truth.
How Many Episodes Does Mousetrap Have?
Mousetrap has 10 episodes.
Netflix lists the show as a limited series, with episodes running roughly around an hour.
All 10 episodes form one complete mystery thriller story.
That makes Mousetrap a relatively easy K-drama to binge compared with longer traditional Korean dramas.
When Was Mousetrap Released?
Mousetrap premiered worldwide on August 28, 2026.
It is a Netflix original Korean series.
International viewers can search for “Mousetrap” directly on Netflix to check availability in their country.
Is Mousetrap Based on a Webtoon?
Yes.
Mousetrap is based on the Kakao Entertainment webtoon Field Mouse.
The original story takes the unsettling idea of someone losing their identity and turns it into a psychological chase.
But the inspiration goes even deeper than the webtoon.
The story is connected to an old Korean folktale.
And that cultural background makes Mousetrap much more interesting for international viewers.
The Korean Folklore Behind Mousetrap
One of the most fascinating things about Mousetrap is its connection to a traditional Korean story sometimes associated with the idea of a field mouse that eats a person’s clipped fingernails.
According to the folktale, a rat eats the discarded nail clippings of a person and transforms into that person.
The fake becomes so convincing that even people around the original person may believe the impostor is real.
Eventually, the real person can find themselves pushed out of their own life.
Mousetrap takes this disturbing old idea and brings it into modern society.
Instead of asking only whether someone can physically look like you, the drama asks a much more contemporary question:
What actually proves that you are you?
Your fingerprints?
Your bank account?
Your phone?
Your passwords?
Your family?
Your memories?
If someone takes control of all of those things, how do you prove that you are the real person?
That is where Mousetrap turns an old Korean folktale into a modern identity thriller.
Why the Title “Mousetrap” Matters
The English title works on several levels.
Moon-jae is searching for “The Rat,” but he is also trapped inside a situation someone else appears to have designed.
Every attempt to escape can pull him deeper into the mystery.
In that sense, the story isn’t simply about catching a rat.
It’s also about discovering who is actually trapped—and who built the trap.
What Makes Mousetrap Different From a Typical Crime K-Drama?
There are no superheroes or supernatural investigators coming to rescue the characters.
Instead, the drama focuses on ordinary human fear.
Moon-jae loses the basic things that allow a person to function in modern society.
His identity.
His money.
His digital access.
His credibility.
The terrifying part is not simply that someone is chasing him.
It’s that the world begins treating someone else as the real version of him.
That gives Mousetrap a psychological dimension beyond a conventional crime thriller.
Ryu Jun-yeol Takes on a Challenging Role
One of the biggest reasons to watch Mousetrap is Ryu Jun-yeol’s performance.
The story requires viewers to constantly question identity and authenticity.
Rather than relying only on dramatic visual differences, the performance has to make viewers notice smaller changes in personality, expression and behavior.
That makes Moon-jae and the identity mystery at the center of the drama particularly interesting.
Why Sul Kyung-gu’s Noja Is Important
Noja is not a traditional hero.
He is a loan shark who initially has his own reasons for pursuing Moon-jae.
But their interests eventually overlap.
This creates an unusual partnership.
Instead of a police detective simply helping an innocent victim, Mousetrap pairs a desperate novelist with a dangerous man who has his own financial motives.
Their relationship adds dark humor, tension and unpredictability to the chase.
Should You Watch Mousetrap?
Mousetrap should appeal especially to viewers who enjoy Korean psychological thrillers, mysteries and stories with major twists.
You may enjoy it if you like dramas involving:
- identity theft
- unreliable characters
- psychological manipulation
- mystery
- crime
- conspiracies
- Korean folklore
- unexpected character connections
It is less suited to viewers looking for a light romance or relaxing weekend drama.
This is a dark mystery designed to make viewers question what they believe.
Is Mousetrap Scary?
Mousetrap is better described as a dark psychological mystery thriller than a traditional horror series.
Its fear comes from paranoia and uncertainty.
Imagine knowing exactly who you are while every digital record, financial account and person around you suggests otherwise.
That idea is frightening precisely because it feels possible in a modern society built around digital identity.
Why International K-Drama Fans Should Know the Folklore
International viewers can enjoy Mousetrap without knowing anything about Korean folklore.
But understanding the field mouse story adds another layer.
The original folktale comes from a much older world.
Mousetrap takes the same fundamental fear—the fear that someone could become you—and places it inside a society of smartphones, fingerprints, passwords, banking records and digital identities.
The technology changes.
The fear doesn’t.
That’s one of the smartest cultural ideas behind the series.
Mousetrap Quick Guide
Title: Mousetrap
Korean title: 들쥐
Release date: August 28, 2026
Platform: Netflix
Country: South Korea
Episodes: 10
Genre: Mystery, Thriller, Crime
Main cast: Ryu Jun-yeol, Sul Kyung-gu, Lee Kyoo-hyung
Director: Kim Hong-sun
Writer: Lee Jae-gon
Based on: Kakao Entertainment webtoon Field Mouse
Main themes: Stolen identity, deception, survival and psychological manipulation
Is Mousetrap Worth Watching?
For fans of Korean thrillers, the premise alone makes Mousetrap worth checking out.
But its biggest strength may be the way it combines a very modern fear—losing control of your digital identity—with a much older Korean folktale.
Ryu Jun-yeol’s identity crisis, Sul Kyung-gu’s unpredictable loan shark and Lee Kyoo-hyung’s investigation create three different paths into the same mystery.
And underneath the chase is one disturbing question:
If everyone believes the impostor is real, what makes you the real person?
That’s what makes Mousetrap more than another identity-theft thriller.
It’s a modern Korean mystery built around a fear that has existed for generations.
Looking for another new Korean series? Read our Four Hands K-drama guide starring Song Kang.
True Taste Korea will continue covering Korean dramas and movies, as well as the Korean culture, food and locations behind the stories international viewers are watching.
This article is based on information available as of August 30, 2026. Streaming availability and program information can change. Check Netflix for the latest information.