Lee Hyukjae, or Eunhyuk, is known best as the main dancer and rapper of Super Junior. He started dancing as an elementary school student and was even in a dance group with his friends called SRD (Song, Rap, Dance). Growing up, his family did not have a lot of money, but pulling together what they had, they were able to pay for him to audition for SM Entertainment in 1999 at the age of 13, with his best friend, Junsu. Unfortunately, Junsu passed the audition while Hyukjae did not. This inspired him to keep trying, and when he auditioned once again, he passed the audition.

          In 2002, Hyukjae was added to a group with Junsu and another trainee named Sungmin. They practiced as an R&B group, untilo Junsu joined a new group called TVXQ!, forcing Sungmin and Hyukjae to disband. After being selected from the advanced dance class, Hyukjae was moved to a practice group including Sungmin and 10 other trainees. When their debut date became official, Hyukjae decided to go by a stage name, Eunhyuk, which means silver jewel. This was because there was a very famous comedian at the time with the exact same name as Hyukjae, so in order to avoid confusion, he became known as Eunhyuk. This group became known as Super Junior 05 (which then became Super Junior 1 year later).

          In 2011, Eunhyuk as well as Henry were both said to be debuting in an all dance/performance unit with four other dancers; Taemin from Shinee, Hyoyeon from Girls Generation, and Kai and Luhan from EXO. This group was called Younique Unit and consists of dancers from different groups within SM Entertainment. Eunhyuk practiced with this group alongside Super Junior, and released a song called "Maxstep," which features all of them dancing.