Monstar

Seol-Chan, the leader of the famed idol group, Men-in-Black, comes back to school after a series of unfortunate events; he runs into Se-yi, a farm girl from New-Zealand, and decides to become her partner.

Seol-Chan, Se-Yi and Seonu, the class president, prepare for the music performance evaluation, but find themselves in big trouble when Seol-Chan forgets all about the evaluation on the test day.

Seol-Chan witnesses Se-Yi and Seonu singing together and feels a twang of envy from their duo; the second year class goes to Gyeongbok Palace to become entangled in an unimaginable event.

Seonu claims his affection for Se-yi and Seol-Chan is left without options; the band comes together in an attempt to solve the problem at hand, but fails to work together due to their emotional discrepancies.

Seol-Chan succeeds in bringing out Do-nam's skill to be able to complete the concert; the All-for-one band proclaims to rejoin the concert, giving no choice but for Seol-Chan to propose a battle-of-the-bands against the All-for-one band.

Seol-Chan continues to be jealous of Se-Yi and Seonu's relationship, and expresses his anger towards Se-Yi, disregarding the practice that is going on for the battle-of-the-bands.