As their high school graduation date draws near, five friends find it difficult to decide on their post-graduation plans. Caught between their own ambitions, family duties, and social expectations, none of the available paths appear to be the right one. Realizing that the future will probably lead them apart, they decide to take one final trip to a hot spring together. However, when one of the girls boards the wrong train and becomes separated from the group, the remaining friends must unite to help their companion find her way back.