Law & Order: Special Victims Unit is set to premiere Season 12 on Wednesday, September 22nd, with the two-hour special Locum. The story finds a foster couple calling Detectives Benson and Stabler to the scene of the crime when their ten-year-old adopted daughter disappears. It soon comes to light that she ran away to meet with a man named Erik Weber (guest star Henry Ian Cusick), whom she met on the internet and whom Benson and Stabler suspect of ulterior motives regarding the girl. Weber denies any wrongdoing, and also expresses romantic interest in Benson. However, as the investigation continues, the detectives realize that the girl's foster parents may be hiding something that could change the entire course of the case.

We recently met up with special guest star Henry Ian Cusick and producer Neal Baer to discuss this upcoming episode. Here is that conversation:

How does your character and Benson become involved in your episodes? And is he really in to her because they say he's going to be a romantic interest or is there an ulterior motive there?

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Henry Ian Cusick: Very early on in the episode you see Benson and my character, Erik Weber, who is a graphic artist; you see them meet and there's a bit of flirtation. Certainly from Erik Weber's point of view he's very interested in Benson and I think it becomes a bit of a rivalry between Stabler and Weber. So yes, there's definitely some - there's definitely an interest -- a strong interest -- from Erik Weber and the Benson character, yeah.

And Neal my next question is for you. What are your plans for the ADAs this season and are there any that haven't been announced yet?

Neal Baer: Well are you asking that because Paula Patton is doing Mission: Impossible?

Oh no. Just because I know you guys have, you know, her coming in for some episodes and some other people coming back. So...

Neal Baer: Right, right.

...I wanted to know if you're planning the revolving or...

Neal Baer: Well Paula Patton is definitely there because she's shooting today. And Christine Lahti is coming back in Episode 9 in a show about alcohol abuse on college campuses which pulls Chris Meloni's character Stabler, again head to head with Christine, her character Sonya Paxton. And then we will likely be announcing another ADA very soon as well.

Okay, great. And are there any past perps or guest stars that you'd like to see return this season?

Neal Baer: Well, Marcia Gay Harden wasn't a perp but she's definitely returning. But she did - let's see, the first episode she almost shot Stabler; the second episode she almost blew him up. So the third episode no telling what will happen because she plays an undercover FBI agent and she's coming back. Gloria Reuben coming back as a U.S. Attorney. Maria Bello will be coming for two episodes this season, and David Krumholtz is working right now. Jennifer Love Hewitt gives a stunning performance as does Joan Cusack opposite Henry Ian Cusick in the first episode. So we've got some really interesting guest stars coming up as well as - but you asked me are there any perps returning? The answer...

Or that you'd like to come back?

Neal Baer: Well, it's so funny you would ask that because I was just talking about that on Friday, and the answer is yes. Probably one of our worst perps ever may return.

Mm-hmm. And can you...

Neal Baer: Are you like - like...

And any hint as to who it is?

Neal Baer: Do you have like a bug in my office or something?

No, I swear.

Neal Baer: No, I don't want to say yet because we're just sort of working on it. But it's funny that you would ask that because we haven't really done that before. And we're actually planning - thinking hard about - so it's like who was your favorite perp basically, coming back. I haven't even talked about it. You're the - it's so funny you would ask. But yes, we're definitely thinking about it.

Just after being on such a, you know, hugely successful long-running show, was it important for you to kind of get right back in to TV right away? And what was it specifically about SVU and this very difficult sort of role that attracted you?

Henry Ian Cusick: You know, I was looking to get back into TV as quickly as possible. I wanted to get away from Desmond. It just seemed that I was no longer Henry Ian Cusick, I was Desmond. So I wanted to sort of like just shed that skin. And then when I met Neal Baer and he called me into his office, I was very charmed by him and his idea for the character. And basically just talking to him and the writer, I was sold really. It was as simple as that. I liked them, I liked their idea, and it just seemed like this would be a really cool thing to get involved with and so I went for it.

How would you basically describe the character of Erik Weber? What do you guys think makes him tick or what do you think his motivations are going to be moving forward in these two episodes?

Henry Ian Cusick: I'll just say something quickly before I let Neal Baer. He's a graphic designer who you meet very early on in the episode. And he's very quickly taken with Mariska Hargitay's character and tries to help them out on a case.

Neal Baer: Well we wanted -- you know, I joked, I know Carlton Cuse really well and I said, "Carlton Cuse, I'm going to like take everybody from Lost." Like I said, "We've run out of all the people from Oz and The Wire so now I've got to go to Lost because Naveen was on last year." And so I loved the show and so I've loved Henry Ian Cusick's character so it was like okay, we have this great two-episode part. And so when we pitched it to him we needed someone who is, you know, extremely charming because Benson's had a number of men interested in her over these gosh, 12 years -- we're starting Season 12 -- and I said, "We need somebody who really has charm and can be kind of a counterpoint to his Stabler in that he's just as smart as Stabler." And we, you know, immediately thought of Henry Ian Cusick for that. And, you know, I think that's what's interesting, particularly in the second episode of the - it's not - it's two episodes but Ian carries us through both episodes. And that is that he, you know - we don't often see someone who kind of can pull Benson in another direction with his own smarts and kind of be a competitor with Stabler. And I like that element of him too that he's, you know, a strong character in and of himself and can stand his own ground. So that's another element that you'll see. And if you go to our bubble Tweet -- we have a 30 second bubble Tweet on atnealbaer on Twitter -- you'll see that there's this moment between Maloney and Ian that's really, you know, tense because, you know, Ian's character is standing his own ground. So that was important to us too.

Law & Order has some incredibly long lists of like really illustrious guest stars, some of which have gone on to win Emmy's for their work. The show is also like an American institution. So how does it feel to be a part of that and were you a fan of the show prior to?

Henry Ian Cusick: You know I feel very honored even just when I was - when I met Neal Baer and he told me about the part and the character and I got very excited about it. And coming off a show like Lost, you know, there were other offers but it was difficult to get excited about anything because, you know, Lost was such a great piece of writing and such a hit show. But I felt I had an input into this character and also knowing who I was going to be working with. And I got very excited as well by the guest stars involved in the show. So yes, it was - I felt very honored to be asked and I find myself in very good company. So, you know, all around it was a pretty good thing to do.

I'm actually excited to see Joan Cusack because she's so great. Was casting of Cusack and a Cusick your idea Neal?

Neal Baer: Was casting...

Henry Ian Cusick: I thought that was very funny, I loved it.

Neal Baer: Was casting the two like with a different letter in the names; was that - sorry, what was your question?

Yes, Joan and Henry. Like how did that work out for the same episode? Were you inspired by their names?

Neal Baer: It was just - no it was funny because I think we cast Henry Ian Cusick first. No, we definitely cast Henry Ian Cusick first because he came in to meet with us and this was a big - because we knew we were doing two episodes at least to start, with him. And so we wanted to have him and then we wanted for this character in the first episode that Joan Cusack plays, we've had great, great luck with comic actors on our show doing these intense parts like Martin Short and Robin Williams. And so it was like okay, let's get Joan. I've loved her in everything and thought she was just always - that there's a real soul to her and heart. So this character needed that because she plays a woman whose child has been kidnapped ten years earlier and she's adopted a foster kid. And I was interested in exploring the issue of what do you do when someone has lost their biological child and they don't know what happened to that child. What does it do to them? And so that's really what that first episode is about and her struggle. And you'll see that Henry Ian Cusick's character has come through to kind of, you know, get involved in finding out what really happened. So it was just sheer serendipity that their names are so close.

I was wondering if your character will appear in more than just the first two hour premiere.

Henry Ian Cusick: Well at the moment no. I think pretty much my story has been told. But then again...

Neal Baer: You never know.

Henry Ian Cusick: never ever know. So - and just listening to what Neal Baer was saying about other people returning, there's always a possibility for, you know, any character to come back.

Neal Baer: Yep.

Henry Ian Cusick: So I guess that's the nature of TV. You know, you never say never, so...

Neal Baer: We had Robin Williams jump into the river and escape and people are still asking is he coming back. So it - you know, you just - you know, and Marcia Gay Harden hasn't been on in about four years I guess so, we don't forget.

And Neal I read that a crossover is planned with SVU and the upcoming Law & Order: Los Angeles.

Neal Baer: Right.

I was wondering if you could elaborate on that.

Neal Baer: Sure.

And if there are any other crossovers planned for the season.

Neal Baer: Well, I wouldn't exactly call it a crossover per se. What happens is in Episode 3 which airs on September 29 starring Jennifer Love Hewitt, in an amazing performance I should add, playing a woman who is confined to her home, afraid to leave because she's been raped by this guy over - a number of times over the years and Mariska Hargitay tries to bring her out. Mariska Hargitay ends up going to Los Angeles because she goes across country - she goes to Detroit and Chicago as well to open rape kits because there's a backlog of rape kits in this country in many, many cities where the rape kits haven't been opened or tested. So they're just sitting in some places literally degenerating, and the reason is that there's not enough money or enough interest. So a lot of perps are going free because the kits haven't been even opened yet or tested as I said. So she's on a mission and that takes her to LA which then takes her to meet Skeet Ulrich's character, Rex Winters from Law & Order: Los Angeles. So what's interesting I think about this is that he appears on Law & Order: Special Victims Unit before he premieres on Law & Order: Los Angeles which is kind of a new thing. So it's a chance for him to make an appearance with Mariska Hargitay which is pretty fun. We've never done anything like that. And then when Law & Order: Los Angeles premieres right after us, that's strictly an LA show so, Mariska Hargitay's not in that. So there's no plans for a further crossover unless we figure out some way that they have to do something in New York for Mariska Hargitay have to come back to LA.

Henry, from the press release it sounds like your character Erik Weber is - he may be a victim of bad decisions in defending the 10-year-old runaway. I just wanted to know, can you talk about Erik's motivations and how he factors in to the investigation?

Henry Ian Cusick: When you first meet Erik Weber he is trying to be a good citizen. And I would - I don't want to give away too much, but that really is just the way Benson and Erik Weber meet up. So yeah, I think he is trying to be, you know, a good citizen. He's trying to help out with the case. And I think you're right, you have - I think you're right, he is a case of mistaken not so much identity, but motives.

Neal Baer: And he's - the girl who plays this role is a just really gifted young actress. We've been very lucky in the past. We've had - you know, we've had Abigail Breslin on, you know and Hayden Panettiere when they were kids, you know, before they, you know, really were known. And now we have Bailee Madison who plays this part in this episode and she's actually better known. She played the daughter of Natalie Portman. So we've got this budding movie star in the first episode as well who's an unbelievably talented young actress. So when you asked about that, she's run away and that's when - that's how we pull Ian's character into the show because he happens to be at the train station and it is a case of mistaken identity. And not mistaken as he said, but there is mistaken motives and it all sort of falls into place after that.

Neal, you just mentioned the small crossover kind of thing between Law & Order: LA and Law & Order: SVU. I wanted to know is there still talk of the two hour Law & Order TV movie in the future?

Neal Baer: Oh, that I don't know because I'm not part of that per se, so I'm not sure. You know I know that - I can tell you that we are, where we are the set used to be -- today is the first day as a matter of fact -- that we are shooting in Chelsea Piers. So it's kind of been a dream for us, particularly Mariska Hargitay because she's had to like go across, you know, in to New Jersey to shoot on our set -- in North Bergen, New Jersey -- in a warehouse. And they've asked me for the last probably since 2001, when are we moving to New York. And it's like, I don't know, you know. And then finally this is it. So what we did is the first four episodes are still shot on - now we call it on location in New Jersey in our old set. And through calamity in Episode 4, Episode 5 opens fresh with our new set which is where the old set was. So that set has been completely torn apart. There is no set any more because it's a brand new set. We're in their old space. So we start fresh with a new set and Paula Patton. So I don't know if that answers - I guess if they had to do - if they were going to do a two hour, they'd have to rebuild the sets or figure out something. But I can tell you that there are no sets anymore.

So you guys got to inherit New York then? It's yours now?

Neal Baer: We did. We're very happy to be at Chelsea Piers and we're thrilled to be in New York.

Neal, is it true that the initial inspiration when the series was created was based on the big New York story about Robert Chambers? And if so, the mother of Jennifer who was murdered, Ellen Levin, did she have anything to do with the initial story and did you consult, you know, that type of thing.

Neal Baer: So do you mean - for which episode? For this season or the original?

The original SVU was based on that sequel had based it on the headline story of Robert Chambers.

Neal Baer: I - well no, the original - the pilot was about two women from Eastern Europe who were - who saw their attacker in New York City. So I don't know how that necessarily connects to - because I wasn't here the first season. But I don't know how that connects to that case. But if you go back and look at the pilot it's about two women who see their - this one woman who sees here torturer and her abuse and kills him.

Okay, just curious. You know you have a very interesting background. How did you meet Dick Wolf?

Neal Baer: How did I meet him? I was doing ER and I was the executive producer of ER. And it was year seven and I was looking to move on because as you recall if you watched ER, almost everybody at that point was gone except for Noah Wyle. So I had worked with the newer cast. And so I was looking, you know, I was like okay, I think it's time. The show had really like for me run its course and what I could give it. And secondly, I had become quite good friends with Mariska Hargitay because Mariska Hargitay was on year five and we really hit it off. That's why I brought Maria on this year and worked, you know, because that was always like kind of a dream to get them, you know, back on because it reminded me of the fun we had on ER. So I was very close with Mariska Hargitay. I wrote a lot for her on ER and I had heard that there was an opening on Law & Order: Special Victims Unit. So I know I left ER on October 13 -- Friday the 13th 2000 -- and I started on Law & Order: Special Victims Unit Friday, October 20. So it was serendipitous. I mean it was - I had - I wouldn't have left ER if I hadn't heard that they were looking for someone to run Law & Order: Special Victims Unit. And because it was Mariska Hargitay, I knew that that was the right thing. And can I tell you a quick story about how Mariska Hargitay got the part on ER which kind of like made everything happen? Well it also ties in because I did an homage on the Ann Margaret episode last season too. So Mariska Hargitay read for a part of Tony's girlfriend and the role required her to go through her purse and take things out. And she was talking about how she was selling vitamins to people and she got fired and she's crying and carrying on. And she's very vulnerable and I thought she was fantastic but the other producers went with someone else. And the next day I saw Mariska Hargitay coming toward John Wells' office and my office was across from John Wells and I said -- and I knew her because I'd met her through a friend before that and they had really been pushing for her. And I said, "What are you doing here?" And she said, "I heard that, you know, you're casting someone else." And I said, "Yeah," And she said, "Well I want that part." And I went in John Wells and John Wells said, well - I said, "Mariska Hargitay wants to see you." And he said, "Well tell her we're casting someone else." And I said, "Well we haven't made the deal yet. We haven't announced it." And he goes no, no, no, tell her we're casting someone else. I said, "No, no, you tell her." And I sent Mariska Hargitay in and about ten minutes later she strolled out - got the part and that's a true story.

Henry Ian Cusick: That's pretty ballsy.

Neal Baer: She's so ballsy. It was like, oh my god. I said to John Wells - and John Wells said, "Well I didn't know what to say to her so I said she got the part." And that's the beginning of the whole long story with Mariska and me working together. And it's just like it's just something I can still see so clearly. So my homage to that was I wrote a scene for her opposite William Atherton last season in the Ann Margaret episode where she kind of played the same role of this woman; she was pretending. She was undercover pretending to be a woman who was very needy and crying. And she and I kind of winked at each other like okay, I guess we've come a long way since then. So sorry, long answer to your question but not one - it's not a story that's told very often.

Why is it that out of all the Law & Orders, besides the obvious fact of the two leads, that it has sustained, out of all of them. You know the first Law & Order it made it 20 years -- great, fantastic but it's history now. It went through a lot of, you know, changes. Criminal Intent went through a big flashing, you know, this last season that different people like; some don't. But it seems like this show has been - has gone it's course and people love it and nothing has ever changed to the extent that it's been something drastic. People love it for what it is. What is it about it that keeps it on it's toes?

Neal Baer: Well I think it's the most political show on television. I mean we're not afraid to take on any kind of subject. And, you know, we'll use a sex crime or a crime against children or the elderly as a way in, but we'll explore really intense issues that could be, you know, issues that, you know, are in the forefront of our culture like torture in Iraq when we did that - we did an amazing show with Elizabeth McGovern playing a doctor who was teaching people how to torture. So we're not afraid to really get into issues. So I think this, as far as I know, is the longest running team. They've got this chemistry; I could say it's the ying and yang. That Mariska Hargitay is the empathy we feel towards victims and he portrays the rage we feel about what's happened to them, even though we sometimes switch it and the two switch and he has the empathy and she has the rage. And they have this chemistry that works so well. The only team I think that has been on longer is Ozzie and Harriett in the comedy. I heard that they were 14 years and we're 12 years. So that says something. And then we try really...

So they're really the glue. Because I mean the other shows touched on a lot of the same subjects...

Neal Baer: Yeah.

...but they seem to be the glue that holds it all together.

Neal Baer: Yes. And also I think we go - we try to - we have a full-time brilliant researcher -- who goes through and gets us lots and lots of details. So we try to really go and give all kinds - we try to take the viewer to places they've never been. If it's geocaching where people go underground in New York on treasure hunts or learning about counterfeit drugs or pet cremation - crazy things going on in New York City, we try to take you things - tell you things and take you to places you don't normally go in a television series so that it has some staying power. And we're really - at least the last time I asked NBC which was a few months ago -- I asked them how many unique viewers of Law & Order: Special Victims Unit do we have a week counting the first run on Wednesday and the repeats on Saturday, the USA syndication and the syndication across the Untied States on weeknights, Monday through Friday. And the answer was 58 million. And we were like, what - what? So it's like - we were like how? And then I started to like add it up and it was like oh god yeah, because if it's on ten times on USA and it has two and a half million that's 25 and 30. So it's like wow. So I don't know, I think there's just something special about - you know to me it's like ER. And I think that seems to help with our show as well because I like - it's fun for me to like play and write for all these people I've always, you know, really admired, you know, their work. It's really a trip.

Henry, maybe you could tell us what the most challenging part of playing this role was for you?

Henry Ian Cusick: The most challenging part - without giving too much away, there's a scene that sort of stretched me as an actor and it comes towards the end of the second - even through it's a two-part, this episode, the premiere is going to be two hours but it will be divided into two later on from my understanding. But towards the end there was a tricky scene there I had to play that I really had to just - it was one of those scenes where I know a lot of actor prepare. But for me it was - I just had to give it up and trust in my fellow actors and trust in my director and trust in the writing and just let it go really. And it could have gone either way. I haven't seen it yet but Neal Baer says it turned out okay.

Neal Baer: I've seen it.

Henry Ian Cusick: So I'm hoping it's okay. But it's just one of those things where you just sort of say well, I'm going to dive in and there you are.

Neal Baer: He blew me away.

Henry Ian Cusick: Well thank you. So that was pretty challenging. But, you know, I have to say Mariska Hargitay, she was delightful and super supportive and very, very helpful to work for me as an actor. She was - it was really surprising. She's done this role for 12 years now and she has all the intensity and all the care about doing this role as if were, you know, the first time. So, you know, kudos to her and to Christopher Meloni as well. You know, they're so passionate about their show and they're very proud of it and you can tell that. So you really have to pick up your game when you're working with them.

So you didn't find any trouble jumping into an already established, you know, team of actors that has such a tremendous rapport between each other?

Henry Ian Cusick: Well yes, you know, there was the nature of the show. You know I was coming from a show where we're running through the jungle and it's a little bit slower. I mean even though it's a dynamic it's the delivery is a little bit slower and it's a little more thoughtful. Here the pace of delivery is different. It's faster and the information is handed over quicker. It's not so introspective. And also you're dealing with New York which I was surprised that it is such a noisy city. And you're filming and you've got crowds shouting and you've got the constant beeping of horns. And I was thinking, how on earth do you ADR this. And from I understand, I've only got two lines to ADR and I can't believe I've only got two lines to do - to ADR because it was such a sort of crowded environment from what I'm used to. I mean when I was filming Lost we'd - you know, we'd be in the jungle. The only thing we had to content with was the sound of the ocean and that was it really.

Neal you talked a little bit about how Olivia is going to finally get something this year that she's wanted for a while. Is that going to play in at all with Erik's character?

Neal Baer: Well that - isn't that a cagey question -- (unintelligible) question. I guess you'll have to watch and see. She wants many things. Well no, I wouldn't say Olivia wants many things. She wants a couple of things and so I think that Ian's character represents something that she indeed might want.

Henry Ian Cusick: That's a good cagey answer.

Neal Baer: Did that answer your question?

Not all. That was a fantastic. Could you tease perhaps a little bit more if it might have something to do with a child?

Neal Baer: I can tease and say that -- what can I say -- I can say that Maria Bello's character has a lot to do with this as well. How's that? That would be Episode 7 and 10.

Neal, I know the rapes backlog story comes from Mariska's passion from the issue. So I was just wondering if she came to you with that idea or you sort of took her passion and decided to make it into a storyline and a full episode.

Neal Baer: Great question because there is a answer to this which is she has a event every year to raise money for Joyful Heart, her foundation. And so I was there this past May in New York and I heard the story of three women up on the stage. one of the stories was about how, you know, they weren't opening the kits. And this guy was out there and he would have been stopped years before. And I leaned over and whispered to one of our writers and I said, "This is your episode." I said, "This is it." Mariska Hargitay testified before Congress last May. So the impetus was actually what always is the impetus for me, a story. A story I hear or a story I read because nothing is stronger than a good - you know, a compelling story. So it started with a story I heard and then we took it from there.

Law & Order: Special Victims Unit will premiere its twelfth season Wednesday, September 22, with the two-hour special Locum beginning at 9:00 pm Eastern on NBC.