Seeking a fresh start, former professional golfer Kazuyoshi Igarashi travels to Hinoshima Island for employment at its development center. Anticipating a remote location with little to offer, he is stunned to find a fully equipped golf course constructed by the locals. Leveraging the coastal landscape, the residents have embraced golf as a pastime. Adding to his astonishment, Kazuyoshi encounters Tonbo Ooi, a young girl who plays exclusively with a 3-iron, a club known for its difficulty. As the ex-pro spends more time with Tonbo and observes her seemingly impossible shots, he begins to view the game differently, rediscovering the joy it can bring.