Uchiage Hanabi unfolds over a summer evening in which Norimichi Shimada and his friends get caught in a deceptively simple debate: when fireworks burst over the Moshimo Festival, do they look round or flat when seen from the side? What sounds like a playful argument soon gives way to a more personal turning point, because the festival becomes the setting for Norimichi's uneasy connection with his classmate Nazuna Oikawa. When Nazuna asks him to run away with her, he is pulled into a choice that feels larger than a single night, with the glow of the fireworks reflecting the pressure of home, the uncertainty of youth, and the possibility of slipping away from everything he knows.
As the evening unravels, a plan that should have led to escape goes wrong, and a mysterious orb in Nazuna's possession introduces the chance of another attempt. Against the shimmer of the summer sky, Uchiage Hanabi traces the fragile mix of longing, impulse, and regret that shapes their fleeting bond, asking whether one brief moment can really change what comes next.
