As the date of their high school graduation approaches, five friends struggle to decide what they will do afterwards. Torn between their aspirations, family obligations, and social pressures, none of their options seem like the correct choice. As they contemplate their decisions, knowing that the future will likely pull them in different directions, they agree to take one last trip to a hot spring together.

However, when one of the girls takes the wrong train and gets separated from her friends, the remaining group must band together to help their friend find her way back.