Welcome to the Kamogawa Diner, where every meal is a mystery ready to be solved. This unique establishment is run by a father–daughter duo who offer more than just mouth-watering meals. They act as ‘food detectives’, delving into the past to produce nostalgia-infused dishes for their hungry clientele.

Among the patrons is a once-renowned pianist whose promising career was marred by a self-inflicted injury. She longs to taste the yakisoba shared with the only man she ever truly loved. The diner also welcomes a man haunted by shadows of regret. His mind races back to the gyoza served by the parents of a lover he once jilted, as he seeks understanding and, perhaps, forgiveness.