When high school teacher Na Aejoon shows up for work on an ordinary day, he never expects to bump into his favorite celebrity in the hallway. But when his school becomes a filming location for a show starring Choi Siyeol, his bias from the idol group A-One, that's exactly what happenddd! If that's not enough to give a fanboy a heart attack, Siyeol takes an interest in Aejoon and ...