‘Mousetrap’ Recap and Ending Explained: The Identity of The Rat Revealed

Netflix has just released one of its most disturbing Korean thrillers of the year, leaving viewers who binged all ten episodes this weekend grappling with the shocking events. ‘Mousetrap’ transforms a chilling identity theft premise into a psychological rollercoaster, and the finale offers little comfort.

Based on the Kakao webtoon ‘Field Mouse,’ the series draws inspiration from a traditional Korean folktale about a rat that takes on human form by consuming human fingernails. This folklore element serves as the foundation for a modern conspiracy surrounding stolen identities, and the finale finally addresses the question fans have been pondering since the trailer’s release: who is The Rat?

Je Moon-jae, a reclusive novelist, has spent years retreating into his own fictional worlds. His quiet life is shattered when the fingerprint recognition on his phone fails, and his friend, who managed his affairs, vanishes without a trace.

With no means to prove his identity, Moon-jae realizes that someone known as Rat has taken everything from him, including his name and property. He seeks out No-ja, a loan shark who operates a private detective agency and has been searching for Moon-jae for three years after he borrowed money and disappeared.

Initially pursuing Moon-jae for an unpaid debt, No-ja is taken aback when the novelist reappears, asking for help to track down The Rat. The two form an uneasy alliance, despite their differing objectives. Meanwhile, Detective Park Sun-yong begins to unravel the peculiar connection between the two men as the case becomes increasingly bizarre.

The show’s central mystery hinges on a stunning twist that redefines everything viewers believed about Moon-jae. The series reveals that the man claiming to be Moon-jae throughout most of the show is actually the impostor, having taken over the real Yu Min’s life years ago.

This revelation flips the entire identity theft narrative on its head. Yu Min’s appearance in the finale is not physical but rather a manifestation of Moon-jae’s paranoia and guilt, reshaping much of the psychological unraveling that unfolds in the latter half of the season.

Fans have been dissecting every clue hinting at this swap on social media, and it’s clear why the show relied heavily on unreliable narration. The folktale framing of a creature that can literally consume someone’s identity serves as a thematic reflection of a more human form of theft, rooted in envy, desperation, and years of meticulous deceit.

The finale’s climax occurs far from Seoul, with the final confrontation taking place on a ship headed for Jeju. Here, Yu Min plans to disappear and expose Moon-jae as the true impostor. In the ensuing struggle, Moon-jae opts to kill his rival to safeguard the identity he has constructed, leading to Yu Min’s fall into the sea.

With no body found, Moon-jae claims self-defense, while Detective Sun-yong, revealed to be Moon-jae’s brother, realizes the story has been staged and accuses him of living a life of impersonation. However, lacking physical evidence or a witness, the police cannot arrest him.

The other significant storyline concludes with less ambiguity. No-ja survives a brutal fight with the criminal Seung-gyu but suffers the loss of his right arm, a permanent consequence of becoming entangled in Moon-jae’s troubles.

In the final moments, Moon-jae legally reclaims his name and home but finds himself isolated and unable to write, trapped within the very lie he created. This bleak, intentionally unsatisfying victory seems to be the point.

For those hoping for further revelations, ‘Mousetrap’ is designed as a limited series, with no second season currently announced. This structure aligns with the story, as the finale resolves the central mystery of The Rat’s identity while leaving Moon-jae ensnared in the repercussions of his own actions.

Despite its closed-ended nature, critics have shared their thoughts on how the mystery concludes overall. The South China Morning Post described the series as a slick yet sluggish mystery thriller, indicating that the pacing may challenge some viewers, even as the twist generates buzz.

Whether ‘Mousetrap’ becomes one of Netflix’s most discussed Korean exports of the year will likely depend on word of mouth in the coming weeks, especially as more viewers reach the Jeju ferry sequence and begin debating what Moon-jae truly deserved.

Now that the true identity of The Rat has been revealed, do you believe Moon-jae escaped unscathed after stealing Yu Min’s entire life, or is his guilt-ridden apartment a life sentence of its own?