Olivia Benson is going to a dark, dark place.
When NBC's "Law & Order: SVU" returns for its 15th season on Sept. 25, the story picks up right where it left off in May — with Mariska Hargitay's detective held captive by serial murderer and rapist William Lewis (Pablo Schreiber from "Orange Is the New Black").
It's a harrowing hour of television — perhaps the most intense episode of "SVU" we've seen. "It's unlike any 'Law & Order' episode ever," showrunner Warren Leight told Yahoo TV at a screening of the premiere earlier this month. "That was our goal."
Here are five things to know about the riveting and disturbing episode:
1. This is Benson as we've never seen her before.
Warning: Benson gets beaten up, pretty badly. Hargitay's beautiful face is covered with bruises and cuts, and it's chilling to see the usually-flinty detective in such a vulnerable state.
"She does not look like Olivia in this episode, she does not sound like Olivia," Leight remarked.
2. Hargitay has her Emmy episode.
The "SVU" star was once a perennial Emmy nominee for Outstanding Lead Actress in a Drama — even winning the award in 2006 — but as more and more cable shows debuted, Hargitay was pushed out of the category. But her tour-de-force performance in this episode will surely get the attention of Emmy voters next year.
"Fifteen years in, for someone to perform like that, it's astounding," Leight said. "I want people to pay attention, to stop taking it for granted."
3. The experience changes Olivia and her colleagues.
While the second episode, which airs right after the premiere, flashes forward a few months, don't think that Olivia's kidnapping and beating will be a thing of the past.
"You'll get the aftershocks of this … she's not a superhero," Leight explained. "There will be post-traumatic stress. Every episode, every case that comes into the squad room now, she'll view through the prism of this experience."
"It's going to reverberate the rest of the season, for Mariska, for her partner," said Richard Belzer, who plays Sgt. John Munch.
Danny Pino, who plays Benson's partner Nick Amaro, added, "It affects all of us."
4. It also tests her romantic relationship.
Perhaps the most affected person in Olivia's life will be her significant other, Det. Brian Cassidy (Dean Winters).
As Winters told us at NBC's fall launch event, "It's intense. It's all new to me. As an actor, I'm dealing with someone that I love who's been attacked, and that's something I've never had to deal with before."
5. "SVU" wants to tell longer stories like this.
Since Leight came on board a few years ago, he's been trying to move the show toward more arcs, rather than just case-of-the-week stories. Leight wants to be able to keep up with cable.
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"Everyone knows if they miss tomorrow night's episode, it'll rerun a hundred times," he said. "If I miss 'Duck Dynasty,' people will be talking about it the next day. The secret formula for Dick [Wolf, the creator] was every episode was self-contained so they can rerun in perpetuity. And that was a great formula until the invention of the DVR."
The actors are grateful for the opportunity to show off their chops. "They say if it's not broken, don't fix it," Winters said. "But just because it's not broken doesn't mean you can't tweak it."
Watch a sneak peek of the episode:
"Law & Order: SVU" premieres Wednesday, Sept. 25 at 9 p.m. on NBC.