Law & Order: Special Victims Unit, the first-spin off of Law & Order, is an American police procedural television series that focuses on crimes of sexual nature. While the victim is often murdered, this is not always the case, and victims often play prominent roles in episodes. The series frequently uses stories that are "ripped from the headlines" or based on real crimes. Such episodes take a real crime and fictionalize it by changing the details. The series premiered on NBC on September 20, 1999, and started its eighteenth season on September 21, 2016.