The whole game is set in San Antonio, Texas, in a post-apocalyptic near future. The player takes the role of Slade, a soldier recruited by Martech Industries, Inc. to retrieve a crystal located in the Dome, in the center of the desolated city. He must make his way through a San Antonio in chaos and fight irradiated inhabitants and mutants to get to the Dome and retrieved the crystal that is supposed to be used to build a new Dome. The end of the game suggests a sequel, but it was never released.
The city is divided in seven sectors, each one ruled by particular factions, all enemies of Slade, with a total of 18 particular levels. The player can travel them by using the three ways of traveling through the sectors.
Slade starts the game with only two weapons, the saber and the shotgun. Along the game, he'll collect more weapons from his enemies. He also has a very useful PDA where he can store a lot of miscellaneous information.