Ace Attorney, known in Japan as Gyakuten Saiban (逆転裁判, Gyakuten Saiban lit. "Turnabout Trial"), is a series of adventure/visual novel games in which players assume the role of a defense attorney in a fictional courtroom setting which is based off of the Japanese legal system to strive to find their clients "not guilty", using investigation, evidence, and cross-examination to prove their case.
The first three games in the series, originally released only in Japan and in Japanese between 2001 and 2004 for the Game Boy Advance platform, have been ported to the Nintendo DS as well as localized into English.
The series has been developed for the DS from the ground up starting in the fourth game. The DS remakes and games in the series take advantage of the DS's features, including the microphone and touchscreen.
The first three games feature and are sometimes referred to by the eponymous main protagonist, Phoenix Wright.
The fourth game, set some years after the previous ones, introduces a new protagonist, Apollo Justice, that takes over for Phoenix.