Mr. Simple (reissue name A-Cha) is the fifth studio album by the South Korean boy band Super Junior. It was released on August 3, 2011, by SM Entertainment, distributed by KMP Holdings and digitally release on August 2. On September 19, 2011, a repackaged edition was released, re-titled A-Cha. It features four new tracks including title track "A-Cha" and "Superman" which was previously released in version B only. This is the group's second album that features ten of the original 13 members and the first being their previous album, Bonamana (2010). At the year end award shows of 2011, the album won the Disk Daesang Award at the 26th Golden Disk Awards and 21st Seoul Music Awards, as well as the Album of the Year at the 13th Mnet Asian Music Awards. The album, including the repackaged version, is listed as the 2nd best-selling album of the year for 2011. According to Gaon Chart, as of the end of December 2012, the album has sold a cumulative total of 543,623 copies domestically. Background and development On March 31, 2011, leader Leeteuk announced during the interview, "At the earliest, we'll be coming out with our fifth album this summer." Leeteuk and Eunhyuk confirmed on their radio show "Super Junior Kiss the Radio" on June 1, 2011, that they had begun recording their upcoming album that day. Heechul tweeted on June 2, 2011, saying that the group "may be going crazy with preparations for our fifth album, but when it's finally released, you're all going to go mad." American dancer Kenny Wormald posted on his official Twitter on July 11, 2011, that he had started the choreography rehearsal for the group's upcoming new single. On the same day, Leeteuk and Eunhyuk stated on their radio show "Super Junior Kiss the Radio" that songwriter Jinu (hitchhiker) had contributed something for the new album. Shim Jae Won, current choreographer and former member of the disbanded SM group Black Beat tweeted two pictures of the choreography practice of the group showing the lower half of their bodies. The first of the teaser photos was released on July 20, 2011, featuring Eunhyuk. Other photos followed, in order of: Donghae, Leeteuk, Shindong, Kyuhyun, Sungmin, Ryeowook, Yesung, Siwon and Heechul. On the same day, it was announced that the album is set for an August 3 release. Music and video The album is mostly synthpop, with the title