In the future, after an unspecified climatic catastrophe, the world is a wasteland. Lots of raiders and bandits are free to rob, maim and murder. That is what they do with the PC's family and that is what causes his lust for revenge. The PC proceeds to walk through the wastes to some place called the "new government" that is nothing but a waste dump from where the self appointed president (which is a part-time farmer) is trying to unite the wasteland. Obviously, he's happy to have a new mercenary willing to get shot for him. And thus, you embark on your crusade to avenge your family and stuff.
I didn't really get much into the story, as I installed and uninstalled the game in the same day.