Young Bin of SF9, the group's leader, has begun his acting career in the musical 'Covertly Greatly: THE LAST' as SF9 celebrates its 10th anniversary in 2024. Debuting on January 30th, Young Bin plays Li Hairang, the son of a high-ranking North Korean official who poses as an aspiring singer in South Korea. The production runs until April 26th at NOL Theater's Daehak-ro Wooricard Hall. This 10th anniversary special performance of the original musical that premiered in 2016 tells the tense story of North Korean special operatives infiltrating a poor Seoul neighborhood under various disguises. Li Hairang is a pivotal character—cold and calculated when executing missions, yet free-spirited and carefree as a struggling musician in South Korea, embodying a complex duality. Young Bin, who has consistently maintained his position as SF9's serious-minded leader, transforms on stage into the remarkably liberated and relaxed Li Hairang, creating an unexpected charm through this contrast. Having previously worked as a rapper, Young Bin showcases new expressions through vocal performances in the musical, maintaining natural flow between dialogue and song. He also demonstrates impressive physicality through group choreography and action sequences, leveraging years of performance experience to create compelling stage presence.