Unlocking Romance: IU and Byun Woo-seok‘s Captivating Chemistry in ’21st Century Great Lady'

Daniel Kim | 2026.04.02

Translation result.
Photo=MBC
[Sports Today reporter Kim Tae-hyung] IU and Byeon Woo-seok bring dazzling married-couple chemistry to MBC’s 21st-Century Daegunbuin.

IU (Seong Hee-ju) and Byeon Woo-seok (Prince Ian), the leads of MBC’s new Friday–Saturday drama 21st-Century Daegunbuin, which premieres on the 10th, described the defining traits of their royal-couple dynamic and discussed their on-screen chemistry.

In the series, Seong Hee-ju (IU) appears to have it all but is constrained by her status as an illegitimate commoner. Prince Ian (Byeon Woo-seok), the king’s son, has spent his life hiding because he has nothing to claim as his own. To change their fates, they enter into a contract marriage.

IU calls them each other’s savior, while Byeon labels their relationship “inseparable,” hinting at a bond that nothing can sever. As the two stars put it, Seong Hee-ju and Prince Ian form an unbreakable couple who may very well rescue one another’s lives—making their romance one to watch.

Audiences are also eager to see how IU and Byeon Woo-seok’s chemistry will bring Seong Hee-ju and Prince Ian’s fragile, important connection to life. IU said, “I briefly crossed paths with Byeon about 10 years ago on another project, but this is our first time acting as full partners. I felt comfortable from the table read onward. On set we shared ideas, supported one another, and built our chemistry together,” highlighting the pair’s solid teamwork.

Byeon echoed that sentiment: “IU and the staff showed so much consideration and support during filming, which really helped our chemistry.” His comment points to a warm, collaborative atmosphere on set. Their mutual trust, thoughtful care, and creative ideas have only heightened anticipation for the story of Seong Hee-ju and Prince Ian.

MBC’s new Friday–Saturday drama 21st-Century Daegunbuin is set in a 21st-century constitutional monarchy version of South Korea. It follows a chaebol woman who, despite having everything, struggles with her commoner status, and a king’s son who has nothing. Together, they fight the constraints of social hierarchy to redefine their destinies.

[Sports Today reporter Kim Tae-hyung ent@stoo.com]
The closest, most fun news ⓒ Sports Today