A story about the behind-the-scenes life of an idol group. Tae Kyung and On Yu are in search of a new member for their idol group. However at the last minute, the member suffers an injury and his twin sister, Mi Nyu, steps in to disguise as him.
Jang Geun Suk as Hwang Tae Kyung
Park Shin Hye Go Mi Nam (Male) / Go Mi Nyu (Female)
Lee Hong Ki as Kang On Yu / Jeremy
Jung Yong Hwa as Kang Shin Woo