Park Bo-young Stars as Identical Twins with a Secret Life Swap in ‘Our Unwritten Seoul’

South Korean actress Park Bo-young is set to mesmerize audiences in her latest dual role as identical twins in the upcoming tvN drama Our Unwritten Seoul, premiering on Saturday, the 24th at 9:20 PM KST.

Our Unwritten Seoul is a romantic coming-of-age drama that tells the story of Yu Mi-ji and Yu Mi-rae, twin sisters whose lives take a dramatic turn when they switch places to help each other navigate the complexities of adulthood. Although they share the same face, their personalities are worlds apart.

Park Bo-young, who plays both sisters, shared insights into differentiating the two characters. “Mi-ji is expressive and reactive, whereas Mi-rae tends to be more reserved and hides her emotions,” she revealed. These nuanced emotional distinctions are what give each character depth despite their indistinguishable looks.

Writer Lee Kang further emphasized their differences through personality types. “Mi-ji is an ENFP—optimistic, sociable, and free-spirited—while Mi-rae embodies an INTJ—thoughtful, strategic, and imaginative,” said Lee, outlining the contrasting mindsets that fuel the drama’s central conflict.

The drama taps into the universal themes of identity and personal growth. What begins as a simple switch to protect a loved one evolves into a journey toward self-discovery, blurred truths, and the pursuit of authentic love.

Promotional stills reveal glimpses of the visually identical yet emotionally divergent twins—one perhaps in a remote village and the other at an urban office—heightening the mystery: who is the real Mi-ji and who is Mi-rae? And can they maintain their lifelong secret promise without being discovered?

With Park Bo-young’s compelling double performance and Lee Kang’s intricate storytelling, Our Unwritten Seoul teases a gripping take on the twin-switch trope rooted in deep emotional resonance. The first episode airs on tvN on June 24 at 9:20 PM KST in South Korea. Don’t miss out on what may be this summer’s most emotionally captivating drama.