In addition to the free demo currently available, the first of three planned DLCs for Mafia III is now available. The DLC, Faster, Baby!, can be purchased by itself or is bundled as a part of the season pass or Deluxe Version of the game and introduces a new storyline in a new part of town. The DLC heavily leans on car chases and car combat as it sets your character off to take down a corrupt Sheriff, apparently channeling it's inner Dukes of Hazard.
The DLC can be downloaded via the Playstation or Xbox stores, or via Steam for PC. More information can be found at the official website.