Dai Gyakuten Saiban: Naruhodou Ryuunosuke no Bouken

This is a prequel game for the Ace Attorney series of text adventure video games. It is the ninth title overall in the series. There are currently no plans for release in the West.

Unlike previous canonical games in the series, which are set in the near future and feature somewhat futuristic technology, Dai Gyakuten Saiban is set near the end of Japan's Meiji period, when the profession of "defense attorney" was still a fairly new concept in Japanese society. The game stars Phoenix Wright's ancestor, Ryuunosuke Naruhodou, as well as a female judicial assistant named Susato Mikotoba. Although the game initially takes place in Japan, the two later travel to the United Kingdom and work cases alongside the renowned detective Sherlock Holmes.

The game incorporates the basic investigation/trial formula used in previous Ace Attorney titles, with some changes especially to the trial portions. Unlike previous games, some text graphics in Dai Gyakuten Saiban use English translations alongside or in place of some of the Japanese terms, such as "cross-examination" and episode titles. Like the other 3DS titles, Professor Layton vs. Phoenix Wright: Ace Attorney and Phoenix Wright: Ace Attorney: Dual Destinies, the game features 3D character models and backgrounds. However, it also expands on the camera work and animations, treating these aspects with special care to help depict Sherlock Holmes's legendary ability to infer details from even the subtlest of movements. For this purpose, actors from the Himawari Theatre Group were brought in for motion capture.