Lee Moo Saeng

Lee Moo Saeng (이무생) is a South Korean actor who built his career doing serious ensemble work before landing breakout roles in some of the highest-rated Korean productions of the 2020s. Born May 10, 1980, in Yongin, Gyeonggi, he studied at Sejong University's Film Arts department and spent years as a dependable supporting performer before wider audiences took notice.

Early credits include Special Affairs Team TEN and the prison drama Prison Playbook (2017). His profile shifted significantly with The World of the Married (2020), the record-breaking JTBC drama that became a cultural moment in Korea and the highest-rated drama in the network's history. He followed with the Netflix sci-fi series The Silent Sea (2021) alongside Bae Doona and Gong Yoo, then the romance drama Thirty-Nine (2022) and the thriller Cleaning Up (2022).

His performances consistently prioritize character texture over screen time, making him one of the more reliable character actors in Korean prestige television. He joins the cast of the tvN colonial espionage drama 100 Day Lie in 2026.