Hello My Teacher (Korean: 건빵선생과 별사탕; RR: Geonbbang Seonsaeng-gwa Byeolsatang; lit.

Na Bo-ri (Gong Hyo-jin) is a 25-year-old woman who desperately wants to be a teacher at the high school she was kicked out of due to a misunderstanding with her teachers over injuring a group of male classmates (she had been a legend there for being a troublemaker and getting into fights).

However, the only thing that enables her to get the coveted job is by signing a contract to essentially babysit Park Tae-in (Gong Yoo), a troublemaker who attends the same high school.

Tae-in, a lonely 20-year-old youth, quickly becomes the "jjang", or "king" of the high school, and enjoys playing mean tricks on Bo-ri whose tough but easygoing personality attracts the majority of her students.

As his relationship with his teacher takes a turn for the worse, Tae-in gradually becomes attracted to her through a series of complicated events.