Mr. Children is a somewhat imperfect K-pop team with leader Eugene who cares only about singing; dancer Jio, the one and only person possessing an idol-like air on the team; vocalist Hyun who used to run a karaoke; and rapper Ricky who learned Korean through rapping. These imperfect members of the group go through intense training under producer Oh Gu-ju who is famous for her spiteful remarks. They become the most famous rookies in 2011, but Sa Hwae-moon, a Korean music industry tycoon who regards Mr. Children as a real pain in the neck, tries everything to make the team members break up. All this happens just seven days before the K-pop Festival! A previous interview by Eugene on his view of K-pop music spreads and rumblings of the team's dissolution are heard. Can Mr. Children survive in this wild music industry and become the idol of the nation?