Nozomi Takemoto, a reclusive first-year high school student, resides in Omuta with her father, a town that once thrived as a coal mining hub. As her summer break nears its end, Nozomi embarks on a bicycle ride to the town's outskirts and stumbles upon a captivating relic: the remnants of a coal mine turret that once symbolized prosperity. Intrigued by this discovery, she delves into the town's history, scouring the library for old records and materials. Along her journey, she crosses paths with a newspaper reporter assigned to cover the town's post-mining era. Through this summer adventure in an unfamiliar town, Nozomi gradually uncovers the hidden chapters of her family's past, connecting her with the experiences of her father and grandparents.