Just Cause II follows a story of Rico Rodriguez, who arrives yet on another fictional island. Previously being on the Caribbean, now he is coming to Panau - an island in Southeast Asia. This time, Rico has to overthrow the dictatorial regime with its leader, Pandak "Baby" Panay and confront his former mentor, Tom Sheldon. When Rico arrives at the island, he discovers three criminal gangs: The Roaches, The Reapers and the Ular Boys. In order to prevail, Rico has to fight all of the three fractions as well.

One of the key features of the game is speed. This game is filled with adrenaline and ways of doing things very fastly. A wide variety of vehicles such as planes, boats, cars and other. A grappling hook is also available for the player as he can make his character fly around like Spider-Man or tie enemies to each other. There is a big choice of weaponry as well - you can have a pistol, two pistols, auto-rifles or even a grenade launcher! Having an open world map provides a player with experience do whatever they please - flying around, making missions or just discovering new things on the island.