A stage event for the Toaru Project announced on Saturday that Yurika Kubo is joining the cast of the television anime adaptation of the A Certain Scientific Accelerator (Toaru Majutsu no Index Gaiden: Toaru Kagaku no Accelerator) manga as Estelle Rosenthal.
The event also revealed a new promo video different from the one posted earlier on Saturday.
The staff also revealed a new key visual.
The series will premiere on AT-X, Tokyo MX, MBS, and BS11 in July. Nobuharu Kamanaka (Big Order) is directing the anime at J.C. Staff. Kenji Sugihara (Clockwork Planet, Shiki) is in charge of series composition. Yohei Yaegashi (Tsūjō Kōgeki ga Zentai Kōgeki de Ni-kai Kōgeki no Okā-san wa Suki desu ka?, Aki no Kanade) is designing the characters. Jin Aketagawa (Children of the Whales, anohana) is sound director, and Maiko Iuchi (A Certain Magical Index, A Certain Scientific Railgun) is returning to compose the music.
Arata Yamaji began the spinoff series about the A Certain Magical Index character Accelerator in Kadokawa's Monthly Comic Dengeki Daioh magazine in 2013. Seven Seas Entertainment is releasing the manga in English.
<!–Dengeki Bunko editor Kazuma Miki announced the A Certain Magical Index III anime season as part of the "A Certain Project 2018" (2018-Nen To Aru Project) at the "Dengeki Bunko Aki no Saiten 2017" (Dengeki Bunko Autumn Festival 2017) event in October 2017. He also said at the time that the project is “not just Index.” A Certain Magical Index III premiered on October 5.
Kazuma Kamachi’s A Certain Magical Index light novel series has inspired two television anime series, a 2013 anime film, and multiple manga adaptations. A Certain Scientific Railgun spinoff manga has also inspired two television anime adaptations and an original video anime (OVA).
Yen Press is releasing the original light novel series in English, and Funimation has released all of the anime adaptations in North America outside of the A Certain Scientific Railgun OVA. Seven Seas Entertainment is releasing the A Certain Scientific Accelerator manga in English, and Yen Press is releasing the A Certain Magical Index manga in English.–>
Sources: AnimeJapan 2019 stage presentation, A Certain Scientific Accelerator anime's website