Song Ah is 29 years old, and going back to college to study music! After an uninspired career in business, she decides to pursue her passion for music. She will face new challenges like being much older than all her peers and not having the support of her family. See what happens when Song Ah meets the successful pianist Joon Young.

Dong Yun returns to Korea and Min Seong throws a welcome party for him. Joon Young, Hyeon Ho, and Jung Kyung plan on playing together as a piano trio, just like they did when they were in middle school. Meanwhile, Song Ah becomes the trio’s publicist and even stands in as Joon Young's music page-turner for a performance.

Song Ah and Joon Young get to know each other a little better. Joon Young, who struggles to express himself through words, begins to open up to Song Ah for the first time. Song Ah feels reassured by Joon Young’s attention. Meanwhile, Song Ah has a birthday party, but Min Seong says she can’t attend.

Joon Young ends up joining Song Ah's friends for her birthday dinner. Awkwardness hangs in the air between Song Ah and Dong Yun, and it's not much better for Joon Young and Jung Kyung either. Meanwhile, as Joon Young prepares for his speech at his old middle school, he tells Song Ah how he truly feels about his career as a classical musician.

After the talk show, Song Ah shares her thoughts with Joon Young about those who have talent and those who don’t. When Joon Young responds with a totally unexpected answer, Song Ah is disappointed. Meanwhile, Joon Young no longer considers Jung Kyung as fondly after she confesses her feelings. Due to his family’s finances, Joon Young looks for ways to obtain more loans. After a long, stressful day, Joon Young calls Song Ah and admits he enjoys her company. The next day, on a date with Joon Young, Song Ah makes a confession of her own.

As the summer internship comes to an end, Song Ah gets some good news from one of her professors at school. She wants to share the news with Joon Young, but he doesn't respond to her message. Meanwhile, Jung Kyung tells Young In that she broke up with Hyeon Ho. After the fall semester begins, Song Ah meets Joon Young at school.

Joon Young struggles to deal with his family's financial difficulties, his messy friendships, and his teacher's oppressive teaching style. However, he finds himself feeling comfortable and smiling whenever he is with Song Ah. Then, weird rumors about their relationship start to spread across campus.

Song Ah becomes all too aware of people saying that Joon Young is on a different level than she is. She loses confidence and keeps trying to distance herself from Joon Young. Meanwhile, Joon Young reacts coldly when he finds Jung Kyung in front of his house. Afterwards, Joon Young calls Song Ah, saying he has something to tell her.

Song Ah and Joon Young finally realize that their feelings are mutual and enjoy blissful moments together. Meanwhile, Hyeon Ho finds out about Joon Young and Song Ah's relationship and becomes angry. For Joon Young, the stress caused by his broken friendship and the seemingly never-ending cycle of preparing for competitions starts building up.

Seong Jae suggests that Joon Young should talk about his family on TV for publicity. Joon Young feels both insulted and ashamed, but he holds his ground. Meanwhile, Song Ah asks Joon Young if she can visit his place. Both at Joon Young's apartment and later on at school, Song Ah keeps feeling Jung Kyung's presence around Joon Young.

Seong Jae finds out that Song Ah and Joon Young are dating and calls her out for a chat. He hurts her feelings with brutal honesty. Later on, Joon Young joins Song Ah on a sudden trip to Daejeon and shows her the neighborhood where he grew up. After an unexpected meeting with his mother, Joon Young opens up to Song Ah about more personal matters.

With Jung Kyung constantly asking Joon Young whether he still has feelings for her, Joon Young once again redelivers his true feelings. Later, Song Ah questions Joon Young about his whereabouts last night after seeing him and Jung Kyung ride off in a taxi. When Director Nah asks Joon Young a favor regarding Jung Kyung, he turns down her request. Meanwhile, Song Ah is going through a hard time herself and makes a decision that should’ve been made a long time ago.

The recording of Yoo Tae Jin playing “Traumerei” goes viral online. However, it turns out to be Joon Young’s play, not Tae Jin’s. Joon Young demands Tae Jin to take the recording down, but he refuses. Jung Kyung helps Joon Young by talking Tae Jin into taking down the recording of “Traumerei”. Song Ah runs into Jung Kyung and hears about Joon Young playing “Traumerei” and what that means to Joon Young. In the end, she decides to end things with Joon Young.

After breaking up with Joon Young, Song Ah continues with her entrance exam as if nothing happened. On the other hand, Joon Young is in pain from the fact that he hurt Song Ah. In spite of the dissuasion, Joon Young decides to quit playing the piano. Meanwhile, Director Nah passes away. At the funeral, when Song Ah tells Joon Young about her recital and her plans as a violinist, Joon Young asks her if he can be her accompanist.

While Joon Young still waits for Song Ah’s answer, Joon Young, Jung Kyung, and Hyeon Ho perform together at Director Nah’s commemoration concert. Later, Song Ah shares the news regarding her admission offer from the graduate school with Joon Young. As Song Ah listens attentively to Joon Young’s piano performance at his recital, she realizes that her feelings toward Joon Young are solid and carefully opens up to him once again. Meanwhile, Song Ah finally bids farewell to her other self and welcomes the new one.