While visiting a golf course on the island made by the residents, Igarashi witnesses Tonbo's incredible super shot. Intrigued by each other's golf skills, they decide to play together again the next day. While playing, Tonbo opens up about her love for the island. Returning at sunset, Gon encourages Igarashi to experience the island's starry sky, under which Tonbo reveals her past.

As Igarashi adjusts to island life, he observes the interactions between Bunpei and Yoko. Golfing daily with Tonbo, he sees how the island has influenced her impressive shots. Inspired by her uninhibited style, Igarashi wants her to try tournament golf. However, he feels there's something unusual about her play. Unexpectedly, a squall hits them on the course.

Igarashi heads to Kagoshima to find a young golfer who can match Tonbo, who refuses to leave the island. Despite visiting several ranges, no one measures up. On the ferry back, Igarashi learns from Yoko that her niece is a junior tournament winner. Excited, he arranges her visit to Hino Island. Days later, a pickup truck arrives by ferry, with the girl sleeping in the back.

The typhoon hit Hinojima directly. At the development center, Tonbo and Tsubura took refuge. Despite the power outage, Tsubura practiced her swings and shared her feelings. After the typhoon, she gifted her 5-wood to Tonbo. Igarashi then found plans for a hidden hole on the island's golf course and took Tonbo to play it.

The children of the island had to write an essay titled "The Last Summer Vacation" at the end of their final middle school summer. After returning from Akurekijima, Tonbo expressed feelings for the island and new resolutions in essay. The islanders were surprised, and Igaiga worked hard to support her. By spring, at the graduation ceremony, Tonbo had grown taller, and hair reached her shoulders.

Igarashi sends Tonbo, now a high schooler, to stay at a golf practice range in Kumamoto run by a friend who trains junior players. When Tonbo tries a driver shot for the first time, the other students are puzzled by her skill. She soon gets a chance to practice at a nearby course, where she meets Hinoki Otowa, a talented junior golfer known for her performance at the Kyushu Junior Championship.

After witnessing Tonbo's golfing style up close, Coach Hajime is determined to unlock her potential by entering her in the Kyushu Women's Championship. However, she must meet the eligibility criteria first. As Tonbo starts her new high school life, things get hectic as she learns to juggle school, going to the practice range, and practicing on the golf course to secure her spot in the tournament.

Tonbo joins her first tournament, playing with a bold, freewheeling golf style that puts her in the lead on day one. On the second day, she's paired with the other top players from the first round: Hinoki, Tsubura, and Ema, who placed second. With Ema fighting for a comeback after a rough past, their group’s round ignites from the very first hole!

The night before the tournament’s final day, Igarashi arrives in Kumamoto. Noticing a change in Tonbo, he offers advice to draw out her strengths.On the last day, Tonbo, with her trainee caddie Nishida, faces challenging, windy conditions. Skillfully using the wind to her advantage, she climbs the leaderboard, making Hinoki, Tsubura, and Ema recognize her as a serious rival for the title.

On the final day of the tournament, Hinoki turns a penalty into a mental reset. Tsubura stays steady with strategic play, while Emma takes a risky shot despite her injured leg. Meanwhile, Tonbo begins to feel the weight of competition, spurring a change in her resolve.

Emma pushes through the pain of her injured leg for the sake of her swing, Hinoki battles her inner limits, and Tsubura stays true to her own style. Watching from the sidelines, Tonbo cheers them on. An intense showdown over a single final stroke builds to a thrilling, unexpected finish.