Si Woo is a songwriter and leader of the group MoBius. While preparing for a concert, he notices that something is wrong with his hearing. He goes to see a doctor only to hear devastating news. With his life crumbling down, he tries to find Moorim School. Meanwhile, Chi Ang comes to Korea to attend the MoBius concert. His father orders him to go to Moorim. The two meet in front of the school and find something strange.

The shield has come down. People at Moorim wonder what caused this to happen. They believe it’s either because of Si Woo or Chi Ang. Si Woo and Chi Ang are now enrolled at Moorim. They don’t get along but as fate has it, they become roommates. They try to get settled in their new school, but it’s not easy.

Si Woo is convinced that Soon Duk had ulterior motives when she helped him. Soon Duk feels somewhat responsible for the situation Si Woo is in and tries to help him. Meanwhile, Chi Ang and Si Woo are assigned to the introductory class and are given tedious chores to do. While doing these chores, their emotions get the best of them and they get in a fight.

In order to avoid being expelled, Si Woo and Chi Ang accept an assignment. They have to go to the Peak of Moorim to bring back an item that represents Moorim. Only one of them will be allowed to stay at Moorim so they both fight to bring back the item. Meanwhile, Chae Yoon is still unable to wake up and is tormented by his nightmares.

After their trip to Peak of Moorim, Si Woo and Chi Ang start to get along. Si Woo decides to stay at Moorim and Chi Ang asks Soon Duk out on a date. Meanwhile, the other students summon Si Woo and Chi Ang to the armoury in the bell tower.

It’s midterms and Si Woo and Chi Ang are up against each other. Chi Ang is determined to win because he believes it will give him a chance to go on a date with Soon Duk. However, Si Woo doesn’t plan on losing either. Meanwhile, the headmaster has something in mind for the comprehensive exam that will shock everyone.

The students wake up and realise that they are trapped inside the armoury. They are given their last exam, which is to escape the room. After making it out alive, they learn a valuable lesson about working together. Soon Duk and Si Woo grew closer through this experience and shares a special moment together. Meanwhile, Chae Yoon meets with Chairman Wang Hao and asks about his past.

The students of Moorim finally go on their long-awaited retreat. Sun Ah is upset because she isn’t allowed to go outside of the hotel during the retreat. Chi Ang plans to express his true feelings for Soon Duk during the retreat. Meanwhile, Soon Duk avoids Si Woo because she feels awkward around him after their first kiss. Despite this, Si Woo tells her how he feels about her.

After the incident of Soon Duk’s kidnapping, things grow tense around Moorim. Sun Ah finds out that the person that was meant to be kidnapped was her instead of Soon Duk. Soon Duk takes care of Chi Ang and Chi Ang’s feelings for her grow deeper. Meanwhile, someone breaks into the headmaster’s office and Moo Song suspects it to be an inside job.

Moo Song announces that Moorim Competition will be held earlier than usual and that he will allow outsiders to participate. He also plans to invite a special professor to prepare the students for the upcoming competition. Chi Ang confesses his love for Soon Duk again. Meanwhile, Bong San finds out that Soon Duk is attending Moorim and bans her from going back to that school. Chi Ang is overwhelmed with the burning desire to become powerful and warns Si Woo not to participate in the competition.

Tae Oh is invited to teach a special class at Moorim. Si Woo and Chi Ang find out that Tae Oh is Soon Duk’s first love. Tae Oh gives advice to each of his students but shows a different side of him when he is with Si Woo. The students are excited to be taught by Tae Oh but are surprised to find out that he isn’t like the other professors.

Finally, the day of Moorim Competition has come. For the first time in 18 years, Moorim brings down the shield and opens its doors to the outside world. During the competition, Soon Duk comes across the people that kidnapped her. Bong San realises who Si Woo is and is shocked. Meanwhile, there are people that want the competition to be ruined and will do whatever they can to accomplish their goals.

Chairman Wang Hao pressures Moo Song to reveal the truth. Moo Song finally reveals the truth about Sun Ah and she is shocked to find out the truth. Meanwhile, Moorim Competition ends prematurely and all the parents rush their kids out of the school. Moorim Association is disappointed in Moorim School and decides to close it down.

Moo Song leaves Moorim and sets off to find Chae Yoon’s long lost son. Chae Yoon also tries to set up a meeting with Moo Song. Beob Gong, the interim headmaster, brings new professors to Moorim. Unable to come back to school, Soon Duk resumes her part-time job. Meanwhile, Chi Ang is determined, more than ever, to get what he wants.

In search of Soon Duk, Chi Ang goes to her house but doesn’t find her there. The professors and the students of Moorim stay to guard the school. Meanwhile, Si Woo and Chi Ang climb to the Peak of Moorim for the Chunuijoo and finally understand the meaning of it.