"Law & Order: SVU" is making the television history books.

NBC has renewed the police procedural for a record 21st season, making it the longest-running live-action primetime series ever on American TV.

"SVU" will pass the previous record of 20 seasons currently held by its parent show, "Law & Order" (which ran from 1990 to 2010) and CBS' "Gunsmoke" (1955-75).

"The Simpsons" remains the leader for any primetime show at 30 seasons, with two more already ordered by Fox. It's also the record holder for number of episodes, currently at 657.

With "SVU's" 21st season comes a milestone for star Mariska Hargitay, whose Lt. Olivia Benson will become the longest-running character in a primetime live-action series. She passes "Gunsmoke's" James Arness and Milburn Stone, as well as Kelsey Grammer who played Frasier Crane on "Cheers" and "Frasier."

"SVU" comes from super producer Dick Wolf, whose original "Law & Order" series launched several spinoffs. None were as successful, though, as "SVU." Much of its success is due to Hargitay, who has been with the series since the pilot.

"“I’m deeply proud to be a part of this groundbreaking show, and humbled to make television history today,” she said. “The longevity and continued success of SVU is a testament not only to the show’s powerful storytelling and ability to connect with viewers, but to its necessity. We have told important stories for 20 years, and we will continue to tell them.”