Yook Sung-jae (육성재) is a South Korean singer and actor born on May 2, 1995, in Yongin, Gyeonggi Province. A member of the group BTOB since 2012, he quickly developed a parallel career as an actor and became one of the most recognizable idols on television.
He makes a few appearances in Monstar, The Heirs or even Reply 1994 before landing his first major role in Plus Nine Boys in 2014, in which he played Kang Min-gu. His popularity skyrocketed in 2015 with Who Are You: School 2015. In it, he plays Gong Tae-kwang, a rebellious yet endearing high school student—a role that made him widely known among drama fans. That same year, he took on a completely different kind of role in the mystery thriller The Village: Achiara's Secret, in which he plays police officer Park Woo-jae.
In 2016, he landed one of his most famous roles in Goblin. In it, he plays Yoo Deok-hwa, an eccentric and unpredictable heir who is connected to the two main supernatural characters. The series' international success has significantly boosted his profile as an actor.
After spending a few more years focusing on his music and television work, he returned in 2020 with Mystic Pop-up Bar. He plays Han Kang-bae, a young man with the strange ability to make people he touches reveal their secrets. In 2022, after completing his military service, he starred in The Golden Spoon, in which he plays Lee Seung-cheon, a poor young man who gets the chance to swap his fate with that of a wealthy heir.
In 2025, Yook Sung-jae reaffirms his interest in fantasy with The Haunted Palace. In it, he plays both Yun Gap and Gang Cheol—a character linked to a supernatural entity—in a sageuk that blends romance, spirits, and exorcism.
He was then announced as the main character of Nine to Six in 2026, playing the role of Han Seon-woo, thus continuing an acting career that is now firmly established alongside his singing career.
