Following the admission of ninth member, E-Young,
Pledis Entertainment announced that After School will be having a comeback at the end of April 2011. They also announced that After School will release their first full-length studio album. Before the release of the album, several actions were made by the agency such as releasing a mini-album for the group leader
Kahi and also the release of
Orange Caramel's "Bangkok City". On 18 April 2011, Pledis released a photo teaser of the album, featuring fourth generation member E-young. The track-listing and three other member photos followed, which were separated into third, second, and first generation members. On the day before the album's release, Pledis uploaded the video of their lead track "Shampoo" and "Let's Step Up!" on their official channel at
YouTube. Their comeback stage was held on
KBS Music Bank and they performed "Shampoo" and "Let's Step Up". The album contains nine new tracks, three re-recorded songs, and a radio edit. Two of the new tracks, "Lean on Time" and "My Bell" are solo songs sung by main vocal members Raina and Jungah. Two songs from the album feature a Pre-School Girl: "Dream" features Yoonjo, who in 2012 debuted in the group
Hello Venus, and "Funky Man", a duet between members
Nana and
Lizzy, features Kyung Min. ==Track listing==