En el estricto instituto de Younghwa, las jóvenes estudiantes se preparan durante su último año de curso para el Día-D, el día del examen de entrada a la universidad. Además del estrés que todo ello conlleva, 4 amigas empezarán a sufrir extraños sucesos relacionados con el obscuro pasado que guarda el instituto.
Late at night, Woo-hyuk working on writing poems is visited by his ex-girlfriend, Nari. He tries to mellow her out only to find that they exchange misunderstandable words with each other. Recalling their travel to the island "JeBu", they finally find something in common to share. Now Nari asks him to travel to somewhere with her.
