Conception

After spending several years of his career in the American animation industry, Daisuke "Dice" Tsutsumi began to wonder whether he would get a platform to tell another part of his identity.^[2] Dice then decided to start an animation project, dedicated on telling a story true to his cultural heritage. Hence, he began to conceptualize a story which were based on a Japanese mythology with a modern twist.^[6] With his project, he sought to shift the common perspective of onis and the notion of good and evil into a different angle.^[7] It was revealed later on October 20, 2022, that Tsutsumi had based the story on the poetry "Onari's Lullaby" written by his late mother, Emi Tsutsumi, who was a poet.^[5]

The environment of the series was largely inspired by Yakushima in the southern Japan, where Dice and Mari Okada often visit. Its forests, along with its vegetations, were made as the reference for the settings of Onari's neighborhood.^[5]

Development

On March 4, 2019, Tonko House, Daisuke Tsutsumi's own animation studio, unveiled the project, dubbed as Oni , as a part of the studio's project slates among other projects such as Leo and Sleepy Pines.^[3][6] The project was revealed to be a CGI animated and stop-motion hybrid television series, produced (and animated) by Tonko House with its animation developed by CG studio Megalis and Japanese stop-motion animation house Dwarf Animation, with the latter responsible for a Netflix animated series, Rilakkuma and Kaoru.^[3][6] The animated series was revealed to be created and directed by Tsutsumi himself. The test footage of Oni was revealed on the first Tonko House Film Festival in spring 2019.^[3][6]

On November 21, 2019, Netflix announced its collaboration with Tonko House, with Netflix joined the production board of Oni and picked up the series to release on the streaming platform.^[2][7][8] Along with the announcement, Daisuke Tsutsumi, Robert Kondo and Kane Lee of Tonko House were revealed as executive producers of the series with Sara K. Sampson serving as the sole producer.^[7][8]

On June 2, 2022, the television series was officially titled as Oni: Thunder God's Tale.^[9] It would be released as limited series consisting of four episodes with Mari Okada revealed as the main writer of the series ever since 2021.^{[9][10][11][12]} CG studios, Marza and Anima were revealed to have joined the animation development.^[11][13]

Casting

The casting of the limited series was revealed on June 2, 2022.^[9][10][12] Momona Tamada, Archie Yates, Craig Robinson, Tantoo Cardinal, Brittany Ishibashi, Omar Benson Miller, Anna Akana, Charlet Takahashi Chung, Miyuki Sawashiro, Yuki Matsuzaki, Seth Carr, Robert Kondo, and George Takei were revealed as part of the ensemble voice cast.^[4][13][14]

Marketing

The first teaser trailer of Oni: Thunder God's Tale was released on June 2, 2022, along with various visuals of the series.^[9][10][12] The series were also announced at Annecy Festival 2022 as part of Netflix's "work-in-progress" lineup.^[18] On September 25, 2022, the series were showcased as part of Netflix TUDUM Japan lineup with its release date announced on official channels.^[19][20]