MBC's new Friday-Saturday drama "21st Century Great Lady" is garnering high expectations as it records a complete sell-out of advertisements ahead of its premiere. Set in a 21st-century constitutional monarchy, the story depicts the fate-defining romance between Seong Hee-joo (IU, played by IU)—a conglomerate heiress of commoner origin—and Prince Ian (played by Byun Woo-seok), the king's son who cannot ascend to the throne.

Before its broadcast, the drama ranked first (week 4 of March) and second (week 1 of April) in TV-OTT drama buzz according to Good Data Corporation's FUNdex survey. IU and Byun Woo-seok ranked first and second respectively in the TV-OTT drama actor buzz rankings for the first week of April. Additionally, it was listed among Time magazine's "Most Anticipated Korean Dramas of 2026."

The script was selected as the winner of the 2022 MBC Drama Script Contest, with director Park Jun-hwa in charge of production. The casting of IU and Byun Woo-seok alone generated buzz, as the two actors briefly worked together in 2016's "Moon Lovers: Scarlet Heart Ryeo." Byun Woo-seok shared, "I was very happy to show a long-term chemistry in this work after 10 years," describing the atmosphere on set. IU also stated, "It felt like we had been preparing for 10 years, with almost no awkward moments. Since we worked together in the 10th year, I feel so compatible that I want to work together again 10 years from now."

In the drama, Seong Hee-joo is the CEO of Castle Beauty, possessing everything but limited by her commoner background. Prince Ian is a member of the royal family with noble status but is destined never to ascend the throne. To overcome their respective barriers, the two choose a contract marriage. In the drama, Seong Hee-joo repeatedly requests audiences with Prince Ian, but he rejects her approaches, which have unclear motives. Undeterred, Seong Hee-joo continues to seek meetings with Prince Ian.

All advertisements were sold out before the broadcast, and a broadcasting official stated, "Recently, even dramas that rank first in viewership during the same time slot often fail to sell out advertisements," highlighting the unusual complete sell-out situation of "21st Century Great Lady." IU and Byun Woo-seok are promoting the drama by appearing together in various content, with the "Excuse Me" content featuring the two actors approaching 4 million views. "21st Century Great Lady" premieres on the 10th at 9:40 PM.