Park Bo-young's Twin Sisters Make a Secret Pact in 'Unknown Seoul'

In the premiere episode of tvN's weekend drama 'Unknown Seoul' (미지의 서울), which aired on May 24, 2025, viewers were introduced to twin sisters Yumi-ji (박보영) and Yumi-rae (박보영), who have been inseparable since the beginning of their lives. The episode showcased their journey of swapping lives, capturing the hearts of the audience right from the start.

The first episode achieved impressive ratings, recording an average of 4.2% and a peak of 5.5% among households in the metropolitan area, while nationally it averaged 3.6% with a high of 5%. It also ranked first in its time slot across cable and general programming channels, including a top position in the target demographic of viewers aged 20-49 (Nielsen Korea).

Yumi-ji, who had to give up her athletic dreams due to an injury, now lives in the village of Duhong-ri, caring for her grandmother and working as a dedicated laborer. In contrast, her sister Yumi-rae is a top student working for a public enterprise in Seoul. Despite their mother's (장영남) and the neighbor's (김선영) constant comparisons urging Yumi-ji to find a job, it only deepened her resentment towards Yumi-rae.

Unbeknownst to the villagers, Yumi-rae struggles alone in Seoul, having become a target of workplace bullying after assisting a senior who reported corruption. Enduring the indifference and disdain from others, she even received Yumi-ji's concerned phone call with irritation.

The tension between the sisters was eased by Yumi-ji's classmate Lee Ho-soo (박진영), who, upon returning to their hometown, encouraged Yumi-ji to reach out to Yumi-rae, reminding her that despite their issues, they are still the closest of kin.

Taking Ho-soo's words to heart, Yumi-ji decided to visit Yumi-rae in Seoul under the pretext of delivering her mother's homemade dishes. Their reunion revealed a strangely different atmosphere around Yumi-rae, especially when she expressed her determination not to go to work even if it meant risking her health, which deeply unsettled Yumi-ji.

In a moment of panic, Yumi-ji rushed to her sister, only to find Yumi-rae precariously hanging from a window, leading to both of them falling together. Overwhelmed with guilt, sadness, and anger for not recognizing her sister's struggles, Yumi-ji broke down in tears, while Yumi-rae comforted her, apologizing for the situation.

In a heartfelt moment, Yumi-ji proposed a life swap, reminiscent of their childhood when they would take on each other's strengths: "I will live as you, and you will live as me." The twins sealed their secret pact with a pinky promise, leaving viewers eager to see how their story unfolds.

'Unknown Seoul' captivates audiences with its portrayal of two identical twins leading vastly different lives and the emotional journey they embark on to understand each other. Park Bo-young's dual role as Yumi-ji and Yumi-rae showcases her remarkable emotional range, bringing tears to viewers' eyes.

The warm narrative, infused with the unique sensibilities of writer Lee Kang, along with relatable dialogue reflecting the struggles of working individuals, and director Park Shin-woo's contrasting depictions of Seoul and Duhong-ri, create a resonant and comforting experience. With its perfect blend of acting, direction, and storytelling, anticipation builds for the next episode of 'Unknown Seoul,' airing today (May 25) at 9:20 PM.