Lee Byung-hoon began working for broadcasting network MBC in 1970, and made his solo directorial debut in 1974. In 1983, he and writer Shin Bong-seung created the landmark eight-year-long series 500 Years of Joseon, which shifted the genre of historical/period dramas from monotonous historical chronicles into the interpretation of bonafide records like the Annals of the Joseon Dynasty. His follow-up, Kim Jung-soo-penned contemporary drama My Mother's Sea was also popular, with a peak viewership rating of 51.6%. But in 1999 Lee revolutionized the sageuk genre with Hur Jun, the first Koreanperiod drama to focus on a "commoner" historical figure instead of royalty and powerful nobles. Jun Kwang-ryul played Heo Jun, a court physician who wrote Dongui Bogam, one of the pillars of traditional Korean medicine. Hur Jun reached record-breaking viewership ratings of 64%. This was followed by Sangdoin 2001, an adaptation of the Choi In-ho novel about legendary merchant Im Sang-ok, and Lee again cast Jun in the leading role. Journalists coined the term "fusion sageuk" for Lee's attempts to revitalize the genre, transforming the previous lack of accessibility and narrative cliches of period dramas with its viewership of older, male armchair historians, into something more appealing to an increasingly younger demographic of viewers. Sageuk further rose to prominence in 2003 with Dae Jang Geum, whose protagonist Jang Geum first trains in Korean royal court cuisine before becoming Joseon's first female court physician. Domestically, Dae Jang Geum was a big hit, receiving a peak viewership rating of 57.8%. Produced for, it was later exported to 91 countries and became one of the major proponents of the Korean Wave, earning worldwide, and turning actress Lee Young-ae into a superstar in China and an icon for Korean culture. Lee continued directing hit period dramas in succeeding years. Ballad of Seodong is about King Mu of Baekje who falls for Princess Seonhwa of the rival kingdom Silla. Yi San revolved around the love story of King Jeongjo and his concubine Ui-bin Seong. Dong Yi is about Suk-bin Choe who rises from being a palace water maid to the concubine of King Sukjong. The King's Doctor marked theater/film actor Cho Seung-woo's first TV series, in the role of a horse veterinarian who becomes a court physician. Lee has worked with writer Choi Wan-kyu on Hur Jun and Sangdo, writer Kim Yi-young on Yi San, Dong Yi and The King's Doctor, and writer Kim Young-hyun on Dae Jang Geum and Ballad of Seodong. In 2016, Lee collaborated with screenwriter for the 3rd time with MBC's 55th-founding anniversary drama, The Flower in Prison. The drama, about a girl who was born in prison and later becomes an advocate for the poor and unfairly accused people, cast Jin Se-yeon in lead role. The 22-years-old actress has become Lee's youngest female protagonist to date.
