A new set of students at the Kirin High School of Art aspire to become idol stars in the entertainment industry. In the second season, the high school goes into financial bankruptcy and is taken over by Oz Entertainment. The company transfers its young idols-in-training to satisfy a new law that requires underage entertainers to receive 20 hours per week of education and working past 10 p.m. As the teens clash with the current students, rivalries erupt as well as secret crushes and unexpected alliances. 

Shin Hae Sung dreams of a career in music although she only knows it through books rather than actually performing it unlike her best friend Janet, who's a famous solo singer. Jin Yoo Jin, a former child star, flouts school rules and is constantly getting into trouble in his quest to become a hard-core rock star. He also butts heads with JB, who is a member of the famous group I:dn. JB's ex-girlfriend, Rian, who is a member of the famous K-pop group Hershe, wants him back but he starts to develop a crush on Janet. Nana has what it takes to become a top vocalist. But who can achieve the ultimate stardom?