Phoenix Wright: Ace Attorney — Dual Destinies — Takes place approximately a year after Apollo Justice: Ace Attorney, when Phoenix Wright has regained his lawyer badge. It's based on Wright's warning from the first case of the previous game: "Dark times have come for our justice system... And it's up to us to set things right," although everything seems quite normal.
In fact, the justice system fell into the “Dark Age of Justice” 7 years ago: immediately after the unexpected end of the Zach Gramari case and the subsequent UR-1 case a year later. Both prosecutors and lawyers were not above falsifying evidence, manipulating testimony, and other unethical and illegal ways to achieve victory, which shook people's faith in a fair trial. The Wright Anything Agency managed to dispel all rumors and suspicions about Phoenix, and began to move into a new era with a new lawyer.