Pinocchio (Danger)

The song was released digitally on April 17, 2011 through various music portal websites by the distributing and record label agency SM Entertainment.

Accompanying promotional music video was released through YouTube on April 19, 2011.

Throughout the video, the members dance to choreography, gets close ups changing outfit and meets in Luna's set, and a balloon (designed like Pinocchio) appears, startling them.

f(x) made their first live performance stage of the song through appearance in one of the episodes of KBS's Music Bank on April 22, 2011.

The song "Gangsta Boy" was also chosen to be part of the special comeback performances.