Mariska Hargitay is set to host the 78th Primetime Emmy Awards, airing on NBC on Sept. 14.

Law & Order: Special Victims Unit made history when it was renewed for season 21, becoming the longest-running live-action series in TV history. Turning 21 is a major milestone in life and it will be for SVU as well, showrunner Warren Leight tells ET. Its an honor to have a place like this in TV history, he continues. However, not all the changes will be easy for the squad or Benson. RELATED CONTENT:'Law & Order: SVU': The Show's Impact and Legacy 400 Episodes Later (Exclusive)For 'Law & Order' Creator Dick Wolf, A-Level Work Is an Expectation (Exclusive)Past and Current Producers Look Back on Favorite Scenes From 'Law & Order: SVU' (Exclusive)