Ueda, Koike and Keiko are in their fourth year at university. The time limit on their paradise of university is drawing to a close, and they are all feeling impatient in their own ways. Keiko is unable to find a job. Ueda is unsure of Keiko's feelings. Koike is torn between her dream of becoming a novelist and the reality of finding a job. The summer is passing. As if to hold on to their time in paradise, they enjoy a late night of fireworks. In his dreams, Koike sees a strange family picture. The image of the three of them sitting around a make-shift table on a riverbank overgrown with summer grass softly and unobtrusively conveys to the viewer their anxiety about their ambiguous future. The film's sincere image of adolescence is heartbreaking.

The film is set in Karafuto after the radio broadcast of the Imperial Rescript on the Termination of the War. On August 15, 1945, Soviet forces invaded Karafuto. On August 20, the postal telegraph office in Maoka suspended operations and nine of the twelve telephone operators committed suicide by taking potassium cyanide while the city was being invaded.