a casting agent. Siwon became a trainee after being scouted in 2003. Shindong became a trainee in 2004. Ryeowook won the 2004 Chin Chin Youth Festival singing competition and became a trainee just two months before debut in 2005. Kyuhyun then joined the group in 2006, after winning third place in the 2005 Chin Chin Youth Festival. In early 2005, Lee Soo-man announced that he had been preparing for an all-boy project group of twelve members to debut at the end of the year. He called this singing group to be "The Gateway to Stardom of Asia," as most of the members in this group were chosen for their experiences as actors, MCs, models, and radio hosts prior to debut. Heechul and Kibum were already established actors at the time, and most of the other members had already made various kinds of appearances in television and media. Inspired by the rotational concept of Japan's girl group Morning Musume, Lee said that his new group would also experience line-up changes, with new members replacing selected members every year to keep the group constantly young and all-rounded. This concept was then newly introduced to the K-pop market. They are also modelled after Japanese boy band SMAP who are also active as actors and entertainers besides being singers. For a while the group was rumoured to be called O.V.E.R, the acronym for "Obey the Voice for Each Rhythm." However, before the group settled with their current name, the company simply referred to them as juniors, a representation of the members' young ages when they first became SM trainees. After the members showcased their different talents to the company at a picnic, the company finalized their group name to Super Junior, and the first generation of Super Junior officially became Super Junior 05. Super Junior 05 made their pre-debut performance on the Korean channel Mnet on September 11, 2005. At the showcase, they performed various styles of hip-hop dancing, where they danced to B2K's "Take It to the Floor". Han Geng, Eunhyuk, and Donghae also performed a separate dance together, dancing to Usher's "Caught Up." However, the performance did not air on television until May 16, 2006, as a segment in the Super Junior Show, the group's first television documentary. The group officially debuted on SBS' music program Popular Song on November 6, 2005, performing their first single "Twins (Knock Out)". A digital single