Aogashima Island is located 358 km south of Tokyo. The population of the island is only 197. Administratively it's a part of Tokyo but it's so remote that no newspaper is delivered. Masaharu Hirota, a 15-year-old local junior high school student, publishes a local newspaper, Blue Island Times and delivers by himself.
Since there is no high school on the island, those who aspires to continue their education must leave the island. Masaharu is in his last year in the junior high and was given a chance to visit the mainland to see how the life in Tokyo is like. During the trip, Masaharu visits Ryoichi, his older friend who left the island to go to the high school in Tokyo. Ryoichi looked different. He used to be a bright and cheerful guy when he lived on the island but he seems like he lost his energy. Seeing how his best friend has changed, Masaharu begins to doubt about living in the big city.
Then a new girl moves to the island and starts coming to the school.
The new girl, Yuki came to the Island to live with her grandfather. Masaharu is intrigued by this pretty girl. They are in the same grade, and they take classes together.
In fact, there are less than 20 students in the whole school and Yuki and Masaharu are the only students in their grade. Masaharu tries to be friends with Yuki but she doesnft break out of her shell.
One day, the local village official, Mr. Sakaguchi advises Masaharu to take Yuki on a tour on the island. Yuki accepts his invitation and rides on the back of Masaharu's bicycle by which they go around the small island. Yuki was impressed by the beautiful nature of the island. She feels the gentle wind. Gradually she starts to open up.
Masaharu reports on the village tour to Sakaguchi, his mentor in social matters. Sakaguchi suggests that he should take Yuki to a local shrine which has divine influence in bonding people. He told Masaharu to take her there and kiss her. Masaharu was surprised by his word, but Sakaguchi persists.
At last Masaharu makes up his mind and takes Yuki to the shrine. He asks Yuki if he can kiss her but she says "No." Masaharu is devastated. But Yuki acts as if it's not a big deal and continues to be friendly to him.
Yuki gradually gets used to the life on the island. Then one day an accident happens. The school's music teacher injures her hand. She can't play the piano for a chorus concert that everyone's been waiting for. The teacher couldnft find a substitute player but then she sees an article in the Blue Island Times. It says that Yuki is good at playing the piano. The teacher asks Yuki to play but she refuses. Now that it seems the concert is going to be canceled, the chorus members are all disappointed. Masaharu tries to convince Yuki to help the chorus group out but Yuki does not change her mind. Masaharu patiently persuades her until she finally agrees. To everyone's surprise, Yuki's piano is more than passable. Nobody on the island has ever heard anyone play as well as her. Yuki is a well-known pianist who has experience in playing in international competitions.
With Yuki's help, the chorus concert was a great success. Yuki enjoyed playing the piano for the first time in some time. Masaharu was pleased to see Yuki happy.
On the same day, Ryoichi comes back to the island. Masaharu is shocked to hear that his best friend has dropped out of high school. His reservation about living in the big city now turns to fear. Masaharu announces to everyone that he won't go to high school.
A stranger visits the island from the mainland. He is Yuki's piano instructor and he came to coax Yuki to return to Tokyo. Yuki refuses and consequently turns down the chance of being a competitive pianist. Yuki explains to Masaharu the reason why she doesnft want to return to Tokyo. When she was playing her favorite concerto to a large audience, she made a mistake. Traumatized by that experience, she got scared of playing the piano. She escaped to this island. Yuki tells Masaharu that she wants to abandon her pianist career and stay on the island. Masaharu opposes her plan and tells her to go back to her piano career. He tells her, "You're special. What are you doing in a place like this?" His reaction shocks Yuki because she expected him to be supportive. She counter-argues by saying, "Why donft you go to high school? You're just a big baby!"
They both disagree with each otherfs decision for the future. They quarrel.
A couple of days later, Masaharu and Yuki are sitting on a bench looking down at the sea. They both want to make up. Each one is seriously contemplating their future. Yuki decides to play the piano again, but she is still not sure about going back to the stressful urban life. She asks Masaharu if he can go to Tokyo with her. "This is out of the blue, but why don't you come to Tokyo with me." she asks. Yuki was convinced that if Masaharu is with her, she can overcome the stress in the big city. Masaharu didnft know how he can help a genius pianist, but Yuki tells him that all he has to do is to occasionally remind her that she's doing fine. Yuki kisses Masaharu. This persuades him to go to high school in Tokyo.
The day of departure, Masaharu and Yuki board the ship to mainland Tokyo. They are insecure but expectant. This is the first day of their future together.