‘Law & Order: SVU’ hits Season 20: A look back at the many on and offscreen changes

This season will mark “Law & Order: SVU’s” 20th year on the beat investigating sexually based offenses. But while the focus of the NBC drama has remained largely the same for the past two decades, the elite squad known as the Special Victims Unit has not. With the exception of original star (and now executive producer and director) Mariska Hargitay, the drama has survived several major shakeups both on and off camera. As The Times looks ahead to the upcoming 20th season, let’s also take a look back at the stories behind the stories of “Law & Order: SVU.”

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1999-2000 | Season 1

Originally titled “Sex Crimes,” “Law & Order: Special Victims Unit” launches as the first spinoff of the Emmy-winning “Law & Order” in September 1999. Hargitay and Christopher Meloni star as NYPD detectives Olivia Benson and Elliot Stabler. Dean Winters (Det. Brian Cassidy), Michelle Hurd (Det. Monique Jeffries), Richard Belzer (Det. John Munch) and Dann Florek (Capt. Donald Cragen) round out the cast. Belzer reprises his role from the recently axed NBC cop drama “Homicide,” while Florek returns to the role he originated on the first three seasons of the original “Law & Order.”

The premiere episode is, naturally, a crossover with the original series. The series premiere draws 18 million viewers, and will go on to average a little more than 12 for its first season. Midway through the year, NBC moves the show from Mondays at 9 p.m. to Fridays at 10 p.m. The cast changes begin with Winters, who departs the cast after 13 episodes because of his series regular role on the HBO prison drama “Oz.” The show enters the Emmy race in its first season, nabbing nominations in the guest actress in a drama series category for both Jane Alexander and Tracy Pollan.

2000-2001 | Season 2

Showrunner Robert Palm is replaced by David J. Burke and later Neal Baer. Hurd also exits halfway through the season just as the series adds what will become several fan favorites, including Stephanie March as Assistant Dist. Atty. Stephanie Cabot, Tamara Tunie as medical examiner Melinda Warner, BD Wong as forensic psychiatrist George Huang and Ice-T as Det. Fin Tutuola, who now stands as the second-longest-running cast member, behind only Hargitay.

2001-2002 | Season 3

In the wake of 9/11, Dick Wolf is forced to put a planned three-show crossover about an international terrorist scare on hold and images of the Twin Towers are cut from the opening credits. Additionally, the producers dedicate the season to the victims and their families, as well as the first responders, as indicated in the changed voice-over.

2002-2003 | Season 4

The core cast and writing staff remain largely unchanged. However, after jumping from an average of 12 million viewers to more than 15, viewership begins to dip in Season 4.

2003-2004 | Season 5

NBC moves the drama to Tuesdays at 10 p.m. Onscreen, March departs after the fourth episode, in which her character is “killed” and sent into witness protection. She is replaced by Diane Neal, who joins the cast as Assistant Dist. Atty. Casey Novak.

2004-2005 | Season 6

Ratings tick up again in the sixth season and the drama begins to net awards attention, resulting in a Golden Globe win for Hargitay for lead actress in a drama, and later, an Emmy win for Amanda Plummer in the guest actress category.

2005-2006 | Season 7

Both Hargitay and Meloni earn Emmy nominations. The former goes on to win, making her the only actor in the “Law & Order” universe to take home the lead actor/actress prize.

2006-2007 | Season 8

The drama inches towards more serialized storytelling with the introduction of several ongoing stories, including Stabler’s daughter’s DUI and Benson finding her long-lost half-brother. Hargitay is replaced for six episodes by Connie Nielsen, who recurs as Stabler’s temporary partner Detective Dani Beck while Benson is undercover with the FBI. (In real life, the actress was on maternity leave.)

2007-2008 | Season 9

After first introducing him the previous season, Adam Beach joins the cast full time as Det. Chester Lake. Onscreen, Munch is promoted to sergeant. The drama also celebrates its 200th episode this season.

2008-2009 | Season 10

After years of relative stability in front of the camera, a wave of cast changes begins with the exits of Neal after five seasons and Beach after just one. Neal is replaced by Michaela McManus, who comes onboard as Assistant Dist. Atty. Kim Greylek, only to be replaced halfway through the season by returning star March. Behind the scenes, the season ends with tense salary renegotiations between Meloni and Hargitay, and NBC, with the latter threatening to replace its leads. The two sign new deals in May 2009.

2009-2010 | Season 11

In addition to the continued presence of March, Sharon Stone signs on to play Assistant Dist. Atty. Jo Marlowe in a multi-episode arc. Christine Lahti also appears in a multi-episode arc as Exec. Assistant Dist. Atty. Sonya Paxton. (Her character is killed off later in the season.) The show also moves to Wednesdays at 9 p.m. to make room for NBC’s brief 10 p.m. experiment with “The Jay Leno Show.”

2010-2011 | Season 12

So much for order in the court! After signing on to appear in multiple episodes as Assistant Dist. Atty. Mikka Von, Paula Patton exits the series after just one appearance when she lands a starring role in “Mission: Impossible — Ghost Protocol.” Melissa Sagemiller fills the void as another new Assistant Dist. Atty., Gillian Hardwicke. Sagemiller, in turn, is replaced by Francie Swift, who recurs as Assistant Dist. Atty. Sherri West for the latter half of the season.

In November 2010, Neal Baer signs a lucrative multi-year deal with CBS. He subsequently steps down as showrunner at the end of the season. Also behind the scenes, “SVU” moves production to New York from New Jersey to take over the spaces formerly occupied by the original “Law & Order,” which was abruptly canceled in May 2010.

With both Hargitay and Meloni in need of new deals, reports surface about the former eyeing a reduced workload. The plan is to promote the Benson character to a supervisory position and bring in a new female detective (at one point rumored to be played by Jennifer Love Hewitt) to work alongside Meloni’s Stabler. Hargitay signs a new deal in May shortly before NBC’s annual Upfront presentation to advertisers without a deal in place for Meloni. Later that month, talks fall through and Meloni exits the drama after 12 seasons. Hargitay confirms his exit with an emotional statement: “For the past 12 years Chris Meloni has been my partner and friend, both on screen and off. He inspired me every day with his integrity, his extraordinary talent and his commitment to the truth. I love him deeply and will miss him terribly — I’m so excited to see what he’ll do next.”

2011-2012 | Season 13

In addition to Baer’s and Meloni’s departures, Wong also steps down as a series regular for a role on the NBC midseason drama “Awake.” Tunie also moves from the regular cast to recurring. The show returns with a new showrunner in “Law & Order: Criminal Intent” alum Warren Leight and with new series regulars Kelli Giddish and Danny Pino in tow to play incoming detectives Amanda Rollins and Nick Amaro, respectively. To offset the other onscreen changes, both March and Neal are brought back in recurring capacities.

In addition to a new more “gritty” tone, as Neal described in interviews, this season also moves towards more serialized and character-heavy storytelling. This is seen through the introduction of a major new love interest for Hargitay’s character (played by Harry Connick Jr.) as well as the return of former cast member Winters.

2012-2013 | Season 14

After an extensive revolving door in the courthouse, Raul Esparza begins recurring as Assistant Dist. Atty. Rafael Barba in the third episode of the season. However, it’s a different casting that is met with extreme controversy, when Mike Tyson appears in an episode despite his past rape conviction.

2013-2014 | Season 15

The season makes a major turning point for the series, both in front of and behind the camera. Onscreen, the season begins with Olivia kidnapped by a serial rapist named William Lewis (Pablo Schreiber), who will appear several more times during the season. This season also brings Olivia a promotion to sergeant and a baby, whom she decides to foster in the finale.

Behind the scenes, the series says farewell to two of its original stars, Belzer and Florek, leaving Hargitay as the sole remaining cast member from Season 1. In addition to promoting Esparza to series regular, Donal Logue joins the cast in the recurring role of Sgt. Declan Murphy.

2014-2015 | Season 16

While Logue departs for a series regular role on Fox’s “Gotham,” Peter Scanavino joins the cast as Det. Sonny Carisi. At first intended to be a temporary replacement while Pino’s character is demoted to beat-cop duties, Scanavino is promoted to series regular after five episodes. Peter Gallagher also signs on for a recurring role as Deputy Chief William Dodds, the head of the all the SVUs in the NYPD. The season ends with Pino’s departure.

2015-2016 | Season 17

Olivia is promoted once again — this time to lieutenant. Andy Karl joins the cast as Benson’s new No. 2, Sgt. Mike Dodds, the son of Gallagher’s character. However, he’s killed off in the final episode of the season. The Season 17 finale also marks the final episode for Leight, who exits after signing an overall deal with Sony Pictures Television to develop new projects. Meanwhile, Giddish’s real-life pregnancy is written into the series as Rollins welcomes her first child.

2016-2017 | Season 18

Leight is replaced by former “Law & Order” writer and executive producer Rick Eid. This season will also see the drama hit its 400th episode.

The series makes headlines just a month into its new season over an episode seemingly inspired by the sexual misconduct allegations made against then-presidential candidate Donald Trump. In the episode, “Veep” star Gary Cole portrays a wealthy politician whose campaign goes haywire when several women go public with damaging accusations. Originally scheduled to air Oct. 26, the episode is delayed until after the presidential election between Trump and Hillary Clinton. In the wake of Clinton’s surprising defeat, the episode is shelved indefinitely. The following year, the controversial episode — and the many behind-the-scenes delays — are the subject of an episode of another legal drama: “The Good Fight.” The “SVU” episode, titled “Unstoppable,” has yet to air.

2017-2018 | Season 19

After just one season, Eid departs the series to take over as showrunner on another Wolf production, “Chicago P.D.” Enter Michael S. Chernuchin, another series veteran with deep ties to the franchise as a previous show-runner on both the original “Law & Order” and spinoff “Criminal Intent.” Chernuchin leans into the franchise’s rich history by tapping Sam Waterston to reprise his “Law & Order” role as District Attorney Jack McCoy and by bringing on Philip Winchester as Assistant Dist. Atty. Peter Stone, the son of “Law & Order’s” original Assistant Dist. Atty. Ben Stone. Winchester joins the cast midway through the season as a replacement for Esparza, who leaves to work on other projects.