If you enjoy getting lost in the pages of a used book and solving impossible puzzles, this news will delight you. During the Dengeki Bunko Fall Festival Online 2026, the first official trailer for the animated adaptation of Biblia Koshodo no Jiken Techo (The Case Files of Biblia Bookstore) was revealed—a project full of secrets, literature, and deduction that finally has a confirmed release date.

The series is scheduled to premiere in April 2027 and will be produced by the acclaimed studio CloverWorks. Mamoru Kanbe, known for his work on projects like SHOSHIMIN: How to become Ordinary and The Perfect Insider, leads the direction, with Ayako Kurata and Kento Matsui as assistants. The scriptwriting and composition will be handled by Toshiya Ono, while Jun Nakai will oversee character design and chief animation direction, with the soundtrack composed by Takahiro Obata.

The main cast features Riko Akechi as the reserved Shioriko Shinokawa and Shunsuke Takeuchi as the imposing yet hesitant Daisuke Gora. The principal cast also includes Reo Osanai as Ayaka Shinokawa, Wataru Takagi as Shida, Yohei Azakami as Kikuya Kasai, and Saeko Kamijo as Nao Kosuga. The technical team is rounded out by Masatoshi Kai in art direction, Kazuko Nakashima in color, and Teruyuki Kawase in photography direction.

About Biblia Koshodo no Jiken Techo

Biblia Koshodo no Jiken Techo is a highly acclaimed mystery light novel series written by En Mikami and illustrated by Hagu Koshijima, first published in 2011. The series became a phenomenon in Japan with over 6.4 million copies in circulation and multiple nominations for prestigious literary awards. The story previously saw adaptations into live-action TV series in 2013 and a film in 2018, but this new project marks the franchise’s first full jump to animated television format.

The plot is set at the Biblia used bookstore, run by Shioriko Shinokawa, an extremely shy and introverted young woman whose true passion is antique publications. Despite her reserved nature, Shioriko possesses brilliant logical deduction skills, capable of solving major mysteries from the smallest details hidden in pages or the history of volumes. Working alongside her is Daisuke Gora, a tall, sturdy young man who acts as her protector but suffers from dizziness whenever he tries to read a book. Together, they form an unusual pair dedicated to unraveling the secrets and mysteries surrounding the clients who come seeking answers at their shop.

What do you think of the first trailer and CloverWorks’ choice to adapt this mystery story?