In March, at the age of 17, Nina drops out of high school and moves to Tokyo on her own. She's completely lost in the big city. She was encouraged to come here after hearing a certain song she found online. The day she arrives, Nina meets the street musician who plays that song.

Nina starts to cram for school. She promised her parents she would try to get into college. However, she's having a hard time adjusting to her new cram school life, finding it difficult to get into her studies. As she's struggling, she receives a text from Momoka. When Nina visits Momoka's house, she is introduced to a girl her age.

As always, Nina's having a hard time focusing on her studies, but she finds herself having to go to Subaru's school to deliver Subaru's phone. After having a heart to heart, they start opening up to each other. Soon after, the trio set out to put on their first live show as a band.

Subaru's grandmother drops by Tokyo out of the blue. Subaru doesn't want to pursue acting. She wants to be in a band and play music. Now that she's come this far, she needs to say it clearly. But when the moment comes, she finds herself putting on a fake smile and playing the good granddaughter.

A live house that Momoka used to play at asked the girls if they wanted to play a show, and they agree to have their first battle of the bands. As they struggle to meet the ticket sale quota, Momoka gets tickets to a show for her former band.

The three girls practice to level up as a band. Nina is obsessed with beating Diamond Dust, and researches ways to increase their popularity, but she fails to find anything good. That's when Tomo and Rupa approach Nina after having been to see the three girls perform the other day.

Tomo and Rupa join Nina, Subaru, and Momoka, making a five-member band. Momoka informs the rest of an upcoming show they could play, but the five members have such different personalities that it doesn't look like they'd ever come together. Nina and Momoka have different feelings about the band, and they begin the show while their relationship remains strained.

After the live show, Nina and Momoka's fight continues to heat up as they express how they feel. Nina abandons all her escape routes to seriously pursue music professionally. Tomo says she'll quit if Nina and Momoka's rocky relationship continues. Then as Nina starts her first day of her part-time job, Momoka shows up.

Nina's parents come to visit her from her hometown as she continues to dedicate herself to the band. Nina runs away, but she reluctantly returns to her home after everyone convinces her. She tries to talk to her father, but as always, he doesn't see things from her perspective. The next day, her father takes her to her old high school.

Nina and the others arrive at an outdoor music festival. It's a huge venue, and the large stage gets them pumped. Diamond Dust takes the stage and they've gotten better since their last show. Nina and the band absolutely cannot lose. They're going to leave their mark. It's the start of their performance of a lifetime.

In the battle of the bands against Diamond Dust, Nina's band's ticket sales have not even reached half of their sales projection. Meanwhile, Diamond Dust sold out their tickets. The harsh reality comes crashing down. Even then, Nina and the band stay true themselves and begin to play their song.