Summer vacation has emptied a Japanese boys' school of all but three boys: the junior Norio & the seniors Kazuhiko & Naoto. They have no families to return to for the summer, so they spend their days in the empty school. A darkness hangs over the three however: the suicide, three months earlier, of classmate Yu. Norio blames Kazuhiko for Yu's death, because it was well-known that Yu loved Kazuhiko; so Kazuhiko is cruel to Norio, and yet has bad dreams. This uneasy arrangement is exacerbated by the arrival of Kaoru, a student early for the fall - who looks exactly like Yu.