On February 6, 2012, the music video teaser for Ailee's debut song, Heaven, was released. Ailee released the song and the music video for her song, "Heaven", on February 9, 2012. The music video for "Heaven" featured Beast's Gi Kwang.
Ailee made her debut stage performance of "Heaven" on M.net M! Countdown on February 9, 2012 and on SBS Inkigayo on February 11. On February 22, 2012 she released her OST song "Superstar" for KBS's Dream High 2 together with Hyorin & Ji Yeon.
On March 16, Ailee reached the #2 position on KBS Music Bank K-Chart, a significant accomplishment for a rookie.