Included with the third volume of the manga, this story revolves around Houtarou Oreki, who, after being lured by his sister to work as a lifeguard at the local pool, coincidentally reunites with his fellow Classics Club members. When Eru Chitanda notices a mysterious disappearance of a white object from a woman's ear, her curiosity sparks a quest for answers. Hyouka: Motsubeki Mono wa follows Oreki and the club's engaging poolside adventure as they unravel the enigma that captivates Chitanda's inquisitive mind.