Upon being sent to live with relatives in the countryside due to an illness, an emotionally distant adolescent girl becomes obsessed with an abandoned mansion and infatuated with a girl who lives there - a girl who may or may not be real.
Unfortunately the movie When Marnie Was There is not yet available on HBO Max.
| Writing | Joan G. Robinson | Novel |
| Directing | Hiromasa Yonebayashi | Director |
| Writing | Masashi Ando | Screenplay |
| Writing | Keiko Niwa | Screenplay |
| Writing | Hiromasa Yonebayashi | Screenplay |
| Visual Effects | Masashi Ando | Animation Director |
| Production | Koji Hoshino | Producer |
| Production | Yoshiaki Nishimura | Producer |
| Art | Yohei Taneda | Production Design |
| Art | Yohei Taneda | Art Direction |
| Production | Toshio Suzuki | Executive Producer |
| Sound | Priscilla Ahn | Theme Song Performance |
| Sound | Takatsugu Muramatsu | Music |
| Production | Ryoichi Fukuyama | Co-Producer |
| Production | Naoya Fujimaki | Co-Producer |
| Production | Masami Hosokawa | Producer |
| Production | Tomoko Nakayama | Producer |
| Production | Seiji Okuda | Co-Producer |
| Editing | Rie Matsubara | Editor |
| Production | Yohei Taneda | Production Designer |
| Production | Kyohei Ito | Production Manager |
| Production | Shinsuke Nonaka | Production Manager |
| Art | Yoichi Nishikawa | Art Designer |
| Art | Yohei Takamatsu | Art Designer |
| Art | Noboru Yoshida | Art Designer |
| Art | Takashi Omori | Art Designer |
| Sound | Koji Kasamatsu | Sound Director |
| Sound | Eriko Kimura | Sound Director |
| Visual Effects | Masashi Ando | Character Designer |
| Visual Effects | Tsutomu Awata | Key Animation |
| Art | Ayumu Egawa | Background Designer |
| Visual Effects | Shougo Furuya | Key Animation |
| Visual Effects | Makiko Futaki | Key Animation |
| Visual Effects | Takayuki Hamada | Key Animation |
| Visual Effects | Hideki Hamasu | Key Animation |
| Visual Effects | Shinji Hashimoto | Key Animation |
| Visual Effects | Ayako Hata | Key Animation |
| Art | Kosuke Hayashi | Background Designer |
| Art | Sayaka Hirahara | Background Designer |
| Visual Effects | Shunsuke Hirota | Key Animation |
| Visual Effects | Takeshi Honda | Key Animation |
| Visual Effects | Akira Honma | Key Animation |
| Visual Effects | Takeshi Inamura | Animation Director |
| Art | Ryoko Ina | Background Designer |
| Visual Effects | Ei Inoue | Key Animation |
| Art | Yumi Ishii | Background Designer |
| Visual Effects | Megumi Kagawa | Key Animation |
| Art | Ayae Kanbe | Background Designer |
| Art | Naomi Kasugai | Background Designer |
| Visual Effects | Naoko Kawahara | Key Animation |
| Visual Effects | Katsuya Kondo | Key Animation |
| Visual Effects | Kenichi Konishi | Key Animation |
| Visual Effects | Misa Koyasu | Key Animation |
| Art | Tomotaka Kubo | Background Designer |
| Art | Tatsuya Kushida | Background Designer |
| Visual Effects | Kitarou Kousaka | Key Animation |
| Visual Effects | Katsutoshi Nakamura | Key Animation |
| Art | Satoko Nakamura | Background Designer |
| Art | Yuka Nitta | Background Designer |
| Art | Kazuo Oga | Background Designer |
| Visual Effects | Hiroyuki Okiura | Key Animation |
| Visual Effects | Akiyo Okuda | Key Animation |
| Visual Effects | Kazuyoshi Onoda | Key Animation |
| Art | Kiyoshi Sameshima | Background Designer |
| Visual Effects | Shinji Suetomi | Key Animation |
| Visual Effects | Michiyo Suzuki | Key Animation |
| Art | Yoji Takeshige | Background Designer |
| Visual Effects | Atsushi Tamura | Key Animation |
| Visual Effects | Atsuko Tanaka | Key Animation |
| Art | Junichi Taniguchi | Background Designer |
| Visual Effects | Ryosuke Tsuchiya | Key Animation |
| Visual Effects | Moe Usami | Key Animation |
| Visual Effects | Naoya Wada | Key Animation |
| Art | Youichi Watanabe | Background Designer |
| Visual Effects | Kenichi Yamada | Key Animation |
| Visual Effects | Hiroomi Yamakawa | Key Animation |
| Visual Effects | Eiji Yamamori | Key Animation |
| Visual Effects | Takaaki Yamashita | Key Animation |
| Art | Kikuyo Yano | Background Designer |
| Visual Effects | Masafumi Yokota | Key Animation |
| Art | Seiko Yoshioka | Background Designer |
| Visual Effects | Atsuko Otani | Key Animation |
| Visual Effects | Shinji Otsuka | Key Animation |
| Production | Ryûji Hayashi | Casting |
| Production | Takuro Okada | Casting |
| Visual Effects | Akihiko Yamashita | Animation Director |
| Camera | Atsushi Okui | Director of Photography |
| Production | Tamaki Kojo | Line Producer |
| Art | Shiho Sato | Background Designer |
| Camera | Kaneko Fujimaki | Additional Photography |
| Art | Eiko Matsushima | Painter |
