During the winter in Toyama in 1962, Tatsuo Mizushima is fretting about his feelings for his classmate Eiko Tsujisawa while agonizing about his upcoming high school examinations. When he was little, he and Eiko had heard that in April of a year when the winter has been very harsh, any couple finding fireflies together needs to get married. However, his family's situation does not allow Tatsuo to continue his worrying about such things for very much longer.
| Directing | Eizō Sugawa | Director |
| Sound | Masatsugu Shinozaki | Original Music Composer |
| Camera | Shinsaku Himeda | Director of Photography |
| Writing | Teru Miyamoto | Original Story |
| Art | Iwao Akune | Art Direction |
| Production | Matsuo Takahashi | Executive Producer |
| Lighting | Tadaaki Shimada | Lighting Technician |
| Production | Hiroaki Kato | Executive Producer |
| Writing | Kyōhei Nakaoka | Screenplay |
| Editing | Jun Nabeshima | Editor |
| Writing | Eizō Sugawa | Screenplay |
| Production | Kiyoshi Fujimoto | Producer |
| Sound | Fujio Satou | Sound Recordist |