The Phoenix Wright: Ace Attorney series games are not just lawyer simulators. They are dramatic visual novels with riveting plot lines.
Admittedly, not all is as it seems in this game, as often witnesses lie. Some even say that in past cases evidence has been fabricated. Thus it becomes your job to find the truth, both by investigating crime scenes and by questioning witnesses and defendants in the courtroom.
Dual Destinies introduces a new system called the Mood Matrix that allows you to tune into the emotions of a witness to see if there is a contradiction in what they are saying and what they are expressing (for example, in the tone of voice). The game also introduces the "Revisualization" system, which helps players to form new conclusions about the case by linking together what they have learned.
Being able to work out who actually committed the crime, especially in cases where the truth gets absurdly tangled in a web of deception and lies, is immensely satisfying. Dual Destinies is really worth the investment, especially if you enjoyed previous titles in the series.