The Great Ace Attorney: Adventures is the ninth installment of the Ace Attorney series of text adventure video games. New gameplay mechanics introduced to the series include Dance of Deduction, in which Ryunosuke must deduce mistakes and oversights in Herlock's overboard logic and uncover new facts, and Summation Examination, in which players must point out discrepancies among jurors' arguments to make their defendant’s case and ultimately secure a "Not Guilty" verdict.

Set in the late 19th century during Japan's Meiji Period and Britain's Victorian era, the game tells the story of an ancestor of Phoenix Wright, Ryunosuke Naruhodo, who works to sleuth out the truth in witnesses’ testimonies and clear his clients’ names in court alongside a cast of characters - including local ace detective Herlock Sholmes.