A pivotal moment occurred when Yeo accompanied a friend interested in theater to a play in Daehangno.
[5][6] Following a two-year hiatus, Yeo Eui-joo consulted a fortune teller who recommended the name change, which led him to adopt his new stage name Mu Jin-sung.
[8] In 2018, Mu get his first lead role in Naver web drama Closer than Uijeongbu, Farther than Sadang, Season 3.
[10] In the same year, Mu was cast as Ki-chan in the romantic comedy web drama Natural Romance, produced by The Korea Environmental Industry & Technology Institute to promote eco-friendly consumption habits.
[12] In 2021, Mu starred in KBS 1TV's Lunar New Year special musical drama Gumiho Recipe.
He landed the role of Yoo-jin, an aspiring genius writer, after winning a competitive audition with rates of 200 to 1.
[20] In July 2024, it was reported that Mu was cast in Director Park Hoon-jung's first drama series The Tyrant.