NFS Underground focuses on the custom kit and import car circuit. It is most commonly compared to the theme featured in the popular The Fast and the Furious movies. So, it is a definite departure from the world of exotic cars and over-the-top police chases that the series was founded on. More than anything, it features a robust customization mode that is intricately sewn into a lengthy franchise-style single-player experience.

It's a world of gorgeous girls, extremely fast racing, stunning graphics, and some of the most impressive vehicle customization ever created. The flexible car customization mode offers up 20 different vehicles, not a huge number, but with all the different options the variety of personalized cars you can create is staggering. These "Customize Your Ride" options take center stage of the gameplay. Underground's single-player mode is intimately tied into unlocking new parts for your car -- both of the performance increasing and aesthetic variety

Like a story, it unfolds as your challengers message you via your in-car video display. There are a few cut scenes now and then, but mostly it is just audio clips and animated heads that deliver your objectives. It works perfectly, however, and is presented seamlessly. With all the different choices that you have this game can keep you busy for quite some time.