B: The Beginning (B: ザ・ビギニング, Bī: Za Beginingu) is an original net animation (ONA) series created by Production I.G and Kazuto Nakazawa.

Both of them are up against the Market Maker, a hidden organization that controls the government of the island to understand the magical powers that Koku has and where they came from.

[9] Kazuto Nakazawa directed the series and designed the characters while also serving as key animation supervisor, Yoshinobu Yamakawa also directed the series alongside Nakazawa, Katsuya Ishida wrote the scripts, and Yoshihiro Ike composed the music.

[3] The theme song "The Perfect World" was performed by guitarist Marty Friedman and Man with a Mission's vocalist Jean-Ken Johnny in collaboration with bassist Ken-Ken and drummer Kōji Fujimoto.

[16] Itsuro Kawasaki is directing the series, with Kazuto Nakazawa serving as chief director, and the rest of the staff and cast are reprising their roles.