Ryuji is a fisherman that has brought up his daughter Ryoko single-handedly. Ryoko and her childhood friend Kazuya have fallen in love. But when Kazuya dies in a tragic accident while diving for coral wood, Ryoko is overcome with grief and, emotionally destroyed, retreats into silent mourning.
Unfortunately the movie Cobalt Blue is not yet available on HBO Max.
| Sound | Joji Sawada | Original Music Composer |
| Writing | Yu Shibuya | Screenplay |
| Production | Hidehisa Yamada | Producer |
| Writing | Makoto Itakura | Screenplay |
| Production | Teruhito Yamashita | Producer |
| Writing | Ayako Miyagi | Original Story |
| Production | Taro Mori | Line Producer |
| Directing | Yosuke Nakagawa | Director |
| Production | Naoki Hashimoto | Producer |
| Writing | Yosuke Nakagawa | Screenplay |
| Art | Sachio Tanida | Decorator |
