Gelegen in het midden van een afgelegen eiland, is de Abyss het laatste onontdekte gebied, een enorm en verraderlijk peilloos gat bewoond door vreemde wezens waar alleen de dapperste avonturiers afdalen op zoek naar oude relikwieën. In de bovenste verdiepingen van de Abyss komt Riko, een meisje dat ervan droomt ontdekkingsreiziger te worden, een mysterieus jongetje tegen.
| Production | 田中翔 | Executive Producer |
| Production | Koichi Watanabe | Executive Producer |
| Sound | Riko Azuna | Theme Song Performance |
| Sound | MYTH&ROID | Theme Song Performance |
| Production | Akinobu Goto | Executive Producer |
| Production | 山崎明日香 | Executive Producer |
| Art | Takeshi Takakura | Art Designer |
| Sound | Hiromitsu Iijima | Music Producer |
| Production | 榊原光広 | Executive Producer |
| Art | Teru Sekiguchi | Art Direction |
| Art | Takumi Sakura | Prop Designer |
| Visual Effects | Yuka Kuroda | Character Designer |
| Production | Daisuke Koma | Executive Producer |
| Production | Fumihiko Shinozaki | Executive Producer |
| Production | Sojiro Arimizu | Producer |
| Production | Hiromichi Uchibayashi | Producer |
| Production | Yusuke Kumamoto | Producer |
| Editing | 谷口和己 | Online Editor |
| Production | Chisaki Hirano | Associate Producer |
| Production | Keisuke Sugawara | Associate Producer |
| Art | Satoru Hirayanagi | Art Designer |
| Art | Mizuka Ueda | Art Designer |
| Art | Yuichi Takayama | Assistant Director of Photography |
| Editing | Chika Ishii | Online Editor |
| Sound | 山田陽 | Sound Mixer |
| Directing | 垪和等 | Assistant Director |
| Writing | 倉田英之 | Series Composition |
| Visual Effects | Kazuchika Kise | Character Designer |
| Writing | つくしあきひと | Comic Book |
| Sound | Toru Noguchi | Sound Effects |
| Art | Osamu Masuyama | Art Direction |
| Editing | 黒澤雅之 | Editor |
| Visual Effects | Miyao Yamashita | Color Designer |
| Camera | Tsunetaka Ema | Director of Photography |
| Sound | Kevin Penkin | Original Music Composer |
| Directing | 小島正幸 | Series Director |
| Sound | 山田陽 | Sound Director |
| Production | Shinpei Yamashita | Producer |
| Sound | Kevin Penkin | Conductor |
| Production | Noritomo Isogai | Producer |
| Production | Nobuhiro Takenaka | Producer |
| Production | Jun Kimura | Producer |
| Sound | Toshihiro Hayano | Sound Recordist |
