Ever since it debuted in 1999, "Law & Order: SVU" has been the best kind of arresting television — surprising, emotional and uncompromising. And now it's about to air its 400th episode!
Each week, millions tune in to see which baddies Lt. Olivia Benson (Mariska Hargitay) and crew will bust their butts trying to take down each week — but let's face it, we also love to goggle at the stream of famous faces taking their turns as guest stars. One even made a special congratulatory video for the gang!
So in honor of this momentous milestone, we present some of our favorite guests of all time — one of whom went on to have an even bigger starring role, as Hargitay's husband!
Debra Messing
Messing played true-crime series host Alicia Harding, whose sister was murdered years earlier. When the cold case of that murder starts heating up, Alicia taunts the killer on the air and an ADA ends up dead. (Season 12, Episode 17, 2012)
Sarah Hyland
A very young Hyland guest-starred as Lily Ramsey, the sister of a woman who claimed she'd been sexually abused by her father years earlier, and detectives worried about whether the girl should remain in her parents' custody. Hyland became a repeat offender in 2009 when she appeared as a student who kills her classmate in "Hothouse." (Season 3, Episode 1, 2001)
Kyle McLachlan
When his elder son kills his younger son, Brett Morton (MacLachlan) shoots the boy in court because he thinks he's a sociopath. McLachlan returned to the show in 2011's "Blood Brothers." (Season 6, Episode 6, 2004)
Amanda Seyfried
Claiming she was raped by three men, Tandi McCain (Seyfried, in one of her first non-soap opera roles) turned out to be covering for the real rapist — her father's boss. (Season 6, Episode 5, 2004)
Dana Delany
Activist Carolyn Spencer's (Delany) son is arrested for raping a teen starlet, and she blames a radio shock jock for his behavior ... then shoots him to gain support for her cause. (Season 6, Episode 3, 2004)
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Brittany Snow
A bipolar teen (Snow) takes her rock star idol's advice and goes off her meds, then mows down pedestrians with her parents' car. The trial then becomes a soapbox for the musician, who is unrepentant about taking medication. (Season 7, Episode 22, 2006)
Elle Fanning
There may be no happy ending for Eden (Fanning) a little girl whose foster parents forced her to sleep in a cage in a barn. (Season 8, Episode 8, 2006)
Nicole "Coco" Austin
Appearing as an adult film star who helps the detectives find a man hiding cameras in women's toilets, Austin — who married "SVU" veteran Ice-T (Det. Odafin Tutuola) in 2002 — made a brief but memorable first appearance on the show. She's appeared two other times: In 2007's "Fights" and 2012's "Theatre Tricks." (Season 5, Episode 25, 2004)
Melissa Joan Hart
Accused of raping one of her students, Sarah Trent (Hart) says he in fact raped her, and she believes he's a sex addict who needs help. (Season 9, Episode 3, 2007)
Terrence Howard
As Los Angeles ADA Joe Dekker, Howard comes East to defend his cousin, who's been accused of raping a woman in her home in this crossover with the short-lived "Law & Order: LA." (Season 12, Episode 21, 2011)
Elizabeth Mitchell
When a piano teacher (Mitchell) confesses to abusing and killing a student, it turns out she's been covering for a loved one. Mitchell is also a repeat offender, from 2003's "Mercy." (Season 12, Episode 20, 2011)
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Jennifer Love Hewitt
Vicky Sayers (Hewitt) lives frightened and alone in her home, visited every few years by a man who rapes her. Det. Benson tracks the serial rapist across multiple states to get her man. (Season 12, Episode 3, 2010)
Patricia Arquette
As a prostitute with a serial killer for a client, Jeannie Kerns (Arquette) agrees to help Det. Benson trap him — but the gambit is not without risk. (Season 14, Episode 9, 2012)
Peter Hermann
True, Hermann's role as attorney Trevor Langan (who in his first episode is hired to defend Det. Benson when she's framed for murder) is really more of a recurring role than a guest one, but who could resist, knowing that his frequent appearances led to sparks with Hargitay? The pair wed in 2004 and have three children. (Season 3, Episode 11, 2002)
Alec Baldwin
Baldwin, known for scrapping with the press in real life, plays an infamous New York Ledger reporter assigned to write a feature on Det. Benson and the Special Victims squad, but he may be far from the objective outsider he seems at first. (Season 15, Episode 18, 2014)
Sophia Bush
Bush first appeared as Det. Erin Lindsay, brought over from "Chicago P.D." in 2014 and has since made four appearances. In her first episode she worked with Det. Benson to take down a child pornography ring and catch a serial killer leaving victims in both their cities.
"Law & Order: SVU" airs Wednesdays at 9 p.m. ET on NBC.
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