It was a Dark Day when the Bombs Fell

The World Defence Initiative (WDI) has sworn to protect the remainders of the world that survived the bombings, as a squad from the American Branch, search for survivors of the bombing and fight a gang called the scavengers that roams the compromised zone, you will have to fight in dangerous situations with limited troop numbers.

I Recommend playing the levels in order, as the story works best with multiple levels played one after another, as sometimes multiple levels represent the same mission.