21st Century Daegunbuin Hits 11.1% in 4 Episodes — Here's How

MBC's 21st Century Daegunbuin crossed into double-digit territory with its fourth episode, recording a nationwide rating of 11.1 percent on April 18, 2026, according to Nielsen Korea. That figure represents the drama's self-record — it launched at 7.8 percent in its first episode and has climbed with each subsequent broadcast. The per-minute peak in episode 4 reached 13.8 percent, and in the 20-to-54 demographic, the drama ranked first for all of Saturday television. In a television environment where double-digit ratings have become increasingly rare for weekend dramas competing against streaming platforms and other broadcast options, these are numbers that mark a significant achievement.

For context, the drama was competing directly on the same weekend with SBS's legal fantasy series Attorney Shin and the Supernatural, which has been one of the season's other strong performers, and JTBC's new psychological drama Everyone Is Fighting Their Own Worthlessness. 21st Century Daegunbuin held the number one position in the national rating across the weekend slot while also topping the metropolitan Seoul-area numbers at 11.3 percent. It was the dominant performer in its weekend window.

The Episode That Moved the Number

Nielsen's ratings data reflects viewer behavior in real time, and the episode 4 structure explains where those viewers were concentrated. The episode opened with the fallout from a paparazzi photograph — Seong Hee-ju (IU) and Lee An Daegun (Byeon Woo-seok) had been photographed together, and the prince chose to confirm the relationship publicly rather than deny it. From that point forward, the episode ran on two simultaneous tracks: Seong Hee-ju working proactively to make the relationship publicly irreversible before royal opposition could mobilize, and the opposition — led by Queen Dowager Yoon I-rang (Kong Seung-yeon) — working to separate them before it was too late.

The drama reached its first major set piece when Seong Hee-ju brought Lee An Daegun to a baseball stadium. The stadium's kiss cam captured them together on the big board — a public moment with thousands of live witnesses and a social media afterlife, which was precisely Seong Hee-ju's intention. Screenshots of the sequence circulated widely after the broadcast, and "야구장 키스타임" (baseball stadium kiss time) became a search trend by morning. The sequence functioned effectively as romantic comedy while simultaneously serving the episode's plot mechanics, which is the kind of dual-purpose scene construction that drives the social sharing and live viewership required to sustain high ratings week after week.

The episode's per-minute peak of 13.8 percent came at its close. Seong Hee-ju accompanied young King Lee Yoon (Kim Eun-ho) on a drive, and the vehicle's brakes failed while in motion. The car accelerated without stopping, with the king aboard. A rescue attempt by the character Min Jeong-wu (Noh Sang-hyeon) was unsuccessful. At the last moment, another car appeared ahead of the runaway vehicle and blocked it. Lee An Daegun stepped out. The episode ended there. Cliffhangers of this construction — combining physical danger, emotional stakes between lead characters, and an unresolved situation — are designed to produce exactly the post-broadcast engagement and anticipation that shows up in the following week's ratings. Episode 5 is scheduled for April 24.

What the Numbers Mean for MBC and the Season

For MBC specifically, the 21st Century Daegunbuin performance represents a timely reversal of a trend that has been difficult for traditional broadcast networks. Korean free-to-air television has seen consistent audience erosion toward streaming platforms over the past several years, and double-digit ratings have become unusual markers — moments that indicate a drama has crossed from ordinary interest into genuine cultural event status.

The drama's growth rate across four episodes — from 7.8 percent to 11.1 percent — is unusual in its speed. Most dramas that achieve double-digit figures do so gradually over longer runs as word of mouth accumulates. 21st Century Daegunbuin has built its audience at a pace that suggests the IU and Byeon Woo-seok combination is drawing viewers who were already ready to watch, rather than converting skeptics through episodes. The 2054 demographic performance — ranking first for all of Saturday in that group — is particularly notable because younger audiences are most likely to be watching on streaming platforms rather than live broadcast, making the demographic win a sign of cross-platform interest rather than just traditional broadcast viewership.

The weekend drama competition will continue to develop as all three competing series settle into their runs. Attorney Shin and the Supernatural, which had been performing strongly before the 21st Century Daegunbuin surge, saw its most recent ratings figure decline to 6.3 percent in the metropolitan area on the same evening. Whether that reflects the competitive pressure of the IU and Byeon Woo-seok drama or the specific content of that episode will become clearer as the season progresses. For now, 21st Century Daegunbuin holds the commanding position in the weekend slot, with momentum pointing upward and a cliffhanger designed to ensure the audience that found it this week has every reason to return next Friday.

What to Know Before Episode 5

For viewers just arriving at the series after hearing about the episode 4 numbers, 21st Century Daegunbuin is worth the context. The show is set in a constitutional monarchy version of Korea — an alternative-history framework in which the royal family exists alongside modern institutions, complete with smartphone cameras, baseball stadiums, and the full machinery of contemporary life. IU plays Seong Hee-ju, a strategically minded commoner drawn into the royal orbit; Byeon Woo-seok plays Lee An Daegun, a prince whose emotional reserve is progressively dismantled by her. The drama airs every Friday and Saturday on MBC.

The series is written by Yoo Ji-won and directed by Park Jun-hwa and Bae Hee-young. Its production involves MBC and Kakao Entertainment, and it streams on KT Genie TV and Tving alongside its live broadcast slot. The supporting cast includes Kong Seung-yeon as the politically calculating Queen Dowager Yoon I-rang, Noh Sang-hyeon as Min Jeong-wu, and Kim Eun-ho as young King Lee Yoon — whose presence in the brake-failure cliffhanger added political stakes to an already tension-filled sequence.

The drama's baseline performance of 7.8 percent in episode 1 already indicated strong viewer interest from the outset. Growth from 7.8 to 11.1 percent represents an unusual trajectory for a domestic drama competing against a fragmented viewing landscape. The combination of a high-concept alternative-history setting, strong star power from both leads, and well-executed romantic comedy set pieces has given the show a sustainable appeal that the first four episodes have consistently reinforced. Whether the ceiling is at 11 percent or whether 21st Century Daegunbuin has further room to climb in the weeks ahead will be one of the Korean drama industry's more closely watched storylines of the spring season.