Things are not what they seem outside as people have been infected by some kind of virus. The government has issued that the town be quarantine, which means that none of the people living there can get out. When you heard the news, you knew that it is time for you to get out of that place. You were working on a car that time, trying to modify it to what you want. You decided to drive out of the town and escape the crazy place. You know that this would be a graveyard, so you decided that you must get out, but the government doesn't want you or any people to get out there.
The whole idea here is to get out of that place. Since that would be a long quest, you need to get as closer as you can to the entrance. You would earn money depending on a few factors in the game. You would use the money to upgrade your car little by little till you can finally get out of that place. The game gets more difficult as you make some progress, so it become more challenging to you as you make some progress.