The opening theme song is titled "Act! Addict! Actors!" (the words represented by the "A3" in the franchise's name), and its CD will go on sale on February 5 with additional solo and instrumental versions. In addition, the TV version of the song will play throughout the streets of Tokyo's Ikebukuro area during Animate Girls Festival 2019 next weekend. Masayoshi Ōishi is producing, writing, and arranging the anime's opening theme song, after doing the same for the game.
"Season Spring & Summer" will run until March 2020, and "Season Autumn & Winter" will run from July to September 2020.
The 20 cast members for the in-story actor groups are reprising their roles from the game. Kaori Nazuka will play Izumi Tachibana, the leader and chief director of Mankai Company. <!–
The newly announced staff members are:
- Assistant Director: Makoto Nakazono
- Art Design: Jyu Ishiguchi
- Clothes Design: Ryō Akizuki
- Art Director: Hiroko Tanabe (Kusanagi)
- Color Key: Yuko Tsumori
- HOA: Tri-Slash
- Graphic Art: Hirofumi Araki
- Compositing Director of Photography: Mayo Suzuki (T2 Studio)
- Editor: Hidemitsu Doi
- Sound Director: Takatoshi Hamano
- Music: Masaru Yokoyama (Black Fox, Mobile Suit Gundam: Iron-Blooded Orphans, Fruits Basket), Kana Hashiguchi (Black Fox)
- Opening Theme Song: Masayoshi Ōishi
- Music Production: Pony Canyon
Keisuke Shinohara (Black Fox) is directing the anime at P.A.WORKS and Studio 3Hz. Mariko Komatsu is adapting the original character designs by Ryō Fujiwara and serving as chief animation director. Naoki Hayashi (Black Fox) is in charge of the series scripts. Infinite is producing.
The A3! game debuted for smartphones in January 2017, reaching two million downloads within a month of its debut. The game has five million downloads as of March 2018. The app also ranked #2 in iOS game sales in Japan two times on January 9 and January 10, 2018. CYBIRD released the game worldwide in English outside of Japan, Hong Kong, Taiwan, Macau, and China in October.
The game features four male actor groups, each themed after a particular season. Players take the role of the producer, and are responsible for training the performance skills of their group.
The game inspired a stage play that debuted at The Galaxy Theatre in Tokyo last summer, and also ran in Kyoto before ending its run at The Galaxy Theatre last November. Another stage play titled Mankai Stage A3! ~Autumn & Winter 2019~ ran at the Nippon Seinenkan Hall in Tokyo from January 31 to February 11, at the Shimonoseki Community Hall in Yamaguchi on February 23 and 24, at the Umeda Arts Theater in Osaka from February 27 to March 3, and at The Galaxy Theatre in Tokyo from March 15 to March 24.