In October 2002, Heechul discovered SM Entertainment's Starlight Casting System on a whim as he was researching entertainment companies. Heechul and his friends traveled to Seoul to audition. Being unfamiliar with the area, Heechul missed the open audition hours, but was casted nevertheless.
Along with Hero (Jaejoong), U-Know (Yunho), and future bandmate Kang-in, SM Entertainment placed them in a small project music group called Four Seasons, with each of the four members representing the four seasons of the year. The prospective group never came through; both Hero and U-Know were chosen to join another all-male singing group DBSK
, which debuted in December 2003. With two members gone, the idea of Four Seasons dropped. Heechul and Kang-in were then placed in Super Junior
along with ten other trainees under the same company. This project group managed through well, and they debuted two years later in November 6, 2005 under the name Super Junior 05, the first generation of Super Junior.
In early 2006, SM Entertainment was beginning to recruit new members for the next Super Junior generation, Super Junior 06, with Heechul still as an undergraduate member of Super Junior. However, plans changed when the company added in a thirteenth member Kyuhyun, and the company declared a halt in forming future Super Junior generations. The group dropped the suffix "05" and became officially credited as Super Junior. The re-polished group hit it big after they released their first CD single "U" the following summer in 2006, which became Super Junior's most successful single in the music charts until the release of "Sorry, Sorry" in March 2009. However, setbacks occurred for the promotions of "U" in the latter half of the year when Heechul suffered a major injury from a car accident that occurred on August 10, 2006, when he was heading back to Seoul from Mokpo, where he went to attend the father of Donghae's funeral. The tires malfunctioned while his car attempted to switch lanes. From this accident, he fractured five places on his left leg including his femur, knee, and ankle which required a 6-hour surgery and sustained several other injuries including a tear to his tongue which required stitches. He was advised to stop all activities for a period of twelve weeks. He was released from the hospital on September 13, 2006 and received outpatient care. He returned to the hospital to have a second surgery to remove some of the iron rods in his leg on October 10 and briefly returned to work in late October to film the final three episodes of the MBC youth sitcom Rainbow Romance while still in a cast and wheelchair. It wasn't until late December when Heechul officially returned to individual activities such as variety show appearances and hosting appearances.
In February 2007 he was able to perform on stage as a member of Super Junior-T, a six-piece trot-singing subgroup of Super Junior while still having a few rods in his leg. He started performing with Super Junior as a whole (whose dance routines are more strenuous than those of Super Junior-T) in late April and early May. The remaining rods were removed in 2008.
Like band mate Kibum, Heechul made his first television appearance as an actor before the debut of Super Junior. He starred in the 2005 teen drama, Sharp 2, which he acted alongside Kibum. Not long afterwards, Heechul appeared in an episode of Loveholic as a chef trainee. After the debut of Super Junior, Heechul teamed with Kibum again to star in the sixth season of Nonstop, alternatively known as Rainbow Romance. In 2006, Heechul starred as the supporting character Gong Min in Bad Family. In 2007, he starred in the popular family drama Golden Bride as Kim Young-soo.
Heechul is also a credible host. Before his music debut, Heechul started his hosting career by being a regular MC for the cable music show Show! Music Tank. Soon after the debut of Super Junior he switched to hosting SBS's Popular Songs. He has also been a radio host of his own radio show, SBS Power FM Youngstreet along with Park Heebon, but the program ended in mid-2006. Aside from acting, singing, and hosting, Heechul also became an active participant in variety shows, making frequent appearances on Heroine 6, Vitamin, Sponge, X-man and Love Letter.
From September 9 to November 9, 2008, Heechul and Kang-in starred in the Korean version of the musical Xanadu, sharing the lead role Sonny. Auditions and casting picks was chosen in a process through reality television (To Be Kang-in and Heechul) to promote the musical.He was also on Good Daddies, as learning to be a good father and care for his "daughter".
See Super Junior
2007 - Golden Bride (SBS)
2006 - Bad Family (SBS)
2005 - Rainbow Romance (MBC)
2005 - Loveholic (KBS2)
2005 - Sharp 2 (KBS2)
2008 - Alvin and The Superband (voice-over)
2007 Attack on the Pin-Up Boys
Sang Ji Young University
Writing fairytales, computers and reading
KPOP group: Super Junior
, Super Junior-T