In Under the September Sky by Lindsay Flanagan, sixteen-year-old Sapphire Sullivan has been fascinated by the same urban legend for years. According to the story, a dark-haired teen named Jett died on the Ring of Fire carnival attraction, and his ghost has been haunting it ever since. She has filled pages with different versions of his life and death, hoping that if she can figure out what really happened, she might finally overcome her fear of the ride. When the carnival returns to town for Labor Day weekend, she writes one more short scene using an old pen that once belonged to her grandfather. Soon afterward, she spots a boy who looks like the Jett she has always pictured. At the same time, Sapphire is dealing with feelings for her longtime crush, Jack, who happens to be the best friend of her cousin Slate, the kid who was raised alongside her like a brother. Something happened between them the previous fall, but he called it a mistake, leaving her unsure of where they stand. Now, with Jett’s legend seeming more real than ever and Jack suddenly back in her orbit, Sapphire begins questioning what’s true, what’s imagined, and whether the stories she tells are connected to what’s happening around her.

I really enjoyed Under the September Sky by Lindsay Flanagan. The title was quite clever, along with naming the main character Sapphire since it’s the birthstone for September. I also appreciated the carnival setting. The Ferris wheels, bright lights, cotton candy, and other end-of-summer details made me feel like I was right there with all the characters. At the same time, the mystery of Jett and the Ring of Fire added just enough of an eerie side to it. I liked Sapphire, too. She's a writer and a bookworm who spends a lot of time inside her own head, and her tendency to imagine different versions of how things could turn out felt believable. I thought the difference between Jett and Jack and how Sapphire is pulled in two directions worked really well. More than once, I found myself wondering whether I had everything figured out or was missing something. There’s also something very relatable about Sapphire being able to write things the way she wants them to turn out but struggling to take chances in her personal life. Anyone looking for a young adult romance mixed with ghosts, urban legends, and a touch of magic should have fun with this one. It's a good choice for those who like a love story that keeps them wondering exactly where reality ends and imagination begins.

Under the September Sky by Lindsay Flanagan follows Sapphire Sullivan, a bookish sixteen-year-old who has spent years hiding her feelings for Jack, her cousin Slate's best friend, because she refuses to make Slate share him too. When the Labor Day carnival rolls into town, Sapphire keeps spotting a mysterious dark-haired boy near the Ring of Fire, a ride tied to a local urban legend about a boy who died on it decades ago. That boy, Jett, has literally stepped out of a story Sapphire wrote, thanks to a magic pen passed down from her grandfather that brings written characters to life. As Sapphire juggles Jett's unsettling pull, her unresolved history with Jack, and family wounds left by her absent mother, the chapters alternate between the present carnival and Jett's own tragic teenage romance with a girl named Elsie decades earlier. Sapphire must decide how to write Jett's story to a proper end while figuring out what she actually wants with Jack.

Under the September Sky by Lindsay Flanagan is a warm, imaginative read, and the title fits beautifully, since the carnival sky becomes the stage where a present-day romance and a decades-old tragedy quietly merge. The dual-timeline structure is the book's biggest strength, letting Jett and Elsie's doomed carnival romance unfold alongside Sapphire's story in a way that builds real emotional payoff by the end. Sapphire is a genuinely likable narrator; her guilt over feeling like a burden and her slow-burn ache for Jack feel authentic, and the late family reconciliation scenes are the emotional high point of the whole book. The "boy brought to life by writing" concept is a clever, tender piece of magical realism that sets this apart from typical carnival romances, and Grandpa's own backstory adds lovely depth to that idea. This book suits fans of small-town YA romance, magical realism, and second-chance love stories, especially readers drawn to contemporary romance with a supernatural touch. It earns its stars for its heartfelt family arc, inventive premise, and satisfying ending.