After being awoken from a daydream by Samantha, she shows you the ropes around the city's underground street racing scene. In Underground, you are an unnamed racer in Olympic City with your friend, Samantha.
In addition, Underground introduced an actual plot to the series for the first time. Consisting of the titular first game in 2003, the open world Underground 2 in 2004, and the portable Underground Rivals in 2005, these games drastically changed the focus and identity of NFS from racing exotic cars in various scenic tracks while being chased by the cops to racing heavily-customized import tuners in urban environments at night when there are no cops around.
Need for Speed: Underground is a sub-series of Electronic Arts's Need for Speed franchise developed by EA Black Box.