[Editor's note: The following contains spoilers through the Season 1 finale of Sex/Life, "This Must Be the Place."]

Let's be very clear about it: If you were worried that Sex/Life would be found lacking in the first part of its title, the first season of the new Netflix drama will quickly prove you wrong. The show focuses on Billie (Sarah Shahi), a woman confronting the fact that while she's a wife and mother of two living in a beautiful house in the suburbs, she's not satisfied by her life with Cooper (Mike Vogel). Instead, she's becoming fixated on memories of her previous life, especially memories of her ex-boyfriend Brad (Adam Demos), and when those memories start to intersect with the present day in unexpected ways, her entire world gets turned upside down.

While not greenlit yet for a second season, the first season ends with a dramatic twist — after eight episodes of struggling with her desires, she goes to Brad for sex, but not for love. When Collider spoke with showrunner Stacy Rukeyser about that choice, she had plenty to say about why it was the right place to end the story (for now), with Mad Men as a reference point, and we also dug into Rukeyser's original inspiration for the series, how Shahi fought to be cast as Billie, and that moment in Episode 3 which might be best described as "big."

To start off, I know the series is based on a book [B. B. Easton's 44 Chapters About 4 Men], but how did you come to the project and what inspired you to work on it?

STACY RUKEYSER: Yeah, so it is inspired by the book, not necessarily based on, but inspired by the book. And I connected very personally with the idea of a wife and mom who misses her wild child single days and can't help but wonder, where did that girl go? What was exciting to me was a chance to create a show that was this nostalgia-fueled, sparkly, fever-dream version of the past, and those incredible single-girl-on-the-town nights, but it's also rooted in this deeper exploration of what happens to us as we grow up and become, allegedly, responsible grownups and all the things that we are expected to give up along the way. It was a chance to try to answer that age-old question, can you have it all?

In terms of that, what was key to making it feel relatable? This is something I know the show is in discussion with, but while she has that 85 percent of a pretty good life, what was key to making sure that viewers weren't saying, "Are you sure you're unsatisfied?"

RUKEYSER: For sure. I mean, I think that there's absolutely an element of wish fulfillment and escapism in both her present and her past, and it was important that it was a fair fight. That it wasn't just an easy answer of what man, or really what version of herself, she should go with. But I think that what's relatable is I think everybody has wondered, what if? And have I made the right choices? And, am I the person I'm supposed to be? And one thing that I think is really important is you see Billie's heart on her sleeve. There's so much vulnerability and truthful emotion there with what she's struggling with. I hope that that has people rooting team Billie, whether they're Team Brad or Team Cooper.

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Image via Netflix

It's so funny you say it like that, because I literally wrote in my notes, Team Brad versus Team Cooper?

RUKEYSER: Yeah. Yeah. And like I said, it was really important that it was not an easy choice, and as the season goes on, the layers are peeled back on both of the men and you understand why Brad is the way that he is and what was the trouble in their relationship, but also what was the trauma that he was dealing with. But again, he's not just the bad boy so that you think, "What are you doing? Be with your husband." And then there's also stuff that's not 100 percent satisfying in her marriage. So, hopefully people will go back and forth over the course of the season.

Of course. What was the process of casting Sarah? Because I feel like that's a key element of making this whole show work.

RUKEYSER: Oh, yeah. The show the series lives or dies on Billie, and Sarah was incredible. I say, someone of Sarah's caliber, she doesn't always audition. I mean, I don't know if she does, but an actress of her caliber doesn't always audition, and Sarah really came in and fought for this role. I mean, she came in, she wasn't satisfied with what she did, she went back to the casting director on her own to retape, I think more than once. And she really fought for this, and she spoke quite honestly about how much she connected with this character and how deeply she felt this identity crisis that she's going through and how much she wanted it.

So, it was incredible, and I do feel like she's so much a part of what works is that she, I always say, she's so gorgeous you can't take your eyes off of her when she's onscreen, but the most gorgeous part of her is her soul. And you really, I think, feel for her and what she's going through. And then when you go flashback to the past, she has such joy just emanating from way down deep and it comes up through this throaty laugh and this megawatt smile that she's got, and it just helps take you on that ride of like, "Oh yeah, I remember those great days of my own."

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Image via Netflix

Not just in terms of Sarah, but also for all the actors, what were conversations like about the level of sexual content and the level of nudity that would be involved?

RUKEYSER: Well, everybody had read the scripts and we were very specific on the page because it was really important to, first of all, understand Billie's journey and to understand what it is that she's missing and why those crazy nights on the town and this impossibly sexy man, why he is so hard to forget and why she's still writing in her journal about him and why she's still wondering, did I make the right choice? Basically. And so, you really had to see that and understand on such a visceral level, what that was like.

And then also, it is a really empowered celebration of female sexuality and desire. Part and parcel of the show is saying that women, particularly wives and mothers, are not also supposed to be ravenous sex goddesses and that is, as it says, the self you're supposed to enjoy while you're young and then give up to become a responsible grownup.

And so this was so much of what the show is saying, is that it's okay to want both and to have desires. We wrote all of that on the page. Each of the intimate scenes is there for furthering the story or character, and it was quite defined. So, everybody knew what the story was and what they were getting into, and they were excited about it and excited for this new way of showing female sexuality and desire. And obviously, we had all female directors, we had an intimacy coordinator, so everybody felt, I think, really safe and free to explore.

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Along those lines, I think we're all very aware of the different standards when it comes to male nudity versus female nudity on screen, which is why Episode 3 featuring a very deliberate moment of full frontal Brad makes an impact. Why was that important to you to include?

RUKEYSER: Most importantly, it's important for Cooper's character. It was important to show how down the rabbit hole obsessed he has gotten, that he is now stalking his wife's ex-boyfriend. It's all internal, there's no dialogue, and Mike Vogel does such an incredible job with it, but what you're seeing is him going, "I should not be doing this. I should not be following him from his office. Now I'm following him from his office. Oh my God, I should not be following him into the gym. Oh my God, I'm following him into the gym. I am buying clothes. I'm working out. I'm obsessive watching him. He's going into the shower. I should not go into the shower. Oh, my God, I'm going into the shower. Now I'm in the shower. I should not look down. I should not look down. I cannot help it. Oh, my God."

So it was not just for titillation's sake. It's a real story point to show how obsessed he is, and that that's what it's come to. And these really weird, mixed feelings that he's having where it is titillating for him to read about his wife's experiences and what happened, and they're acting them out, but it's also maddening and horrifying at the same time. So, that's really where that came from.

Again, so much of what we set out to do was a new look at female desire and sexuality, and so often in films or TV shows that are even allegedly about desire, sexuality, it's still so much from the male point of view. it's really about the kind of sex that the man likes and will the woman agree to, like that kind of sex, or come to like that kind of sex, and the camera hangs on the woman's body and she's objectified, and we talked so much about that this is about her experience. And frankly, the camera hangs on the male bodies a little bit more than on her body because that's her gaze, that's her experience of it.

And so, I really felt like we couldn't do this show without at least one piece of that, and that it's really about Cooper and his character. It's not even really a sexual moment. It's about intimidation and measuring up and all of that.

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Image via Netflix

Was a body double used?

RUKEYSER: No. That's not a body double. I mean, people usually ask is it real or is it a prosthetic?

Yeah, that going to be my follow-up question.

RUKEYSER: Yes, yes. And I can tell you what Adam Demos says about it which is, a gentleman never tells. So, we are leaving that up to the viewer's imagination.

When it comes to the end point for the season, was that always your destination? And what was important to you about making that the final scene?

RUKEYSER: Yeah. So, yes, that was always the end point, and it was controversial, and I knew that it was noisy and risky and would start a conversation. And I can remember talking with my executives at Netflix and saying, "If we're not starting a conversation, then what are we doing?" What I often say about it is that Don Draper comes home at the end of the pilot of Mad Men and you discover that he's married and that he's having affairs, and we love Don Draper and he's charming and rakish, and he's completely allowed to do that.

It's taken Billie eight episodes of heart-wrenching struggle and uncertainty back and forth, and yeah, she runs to Brad. Now, we don't know what happens after she says what she says, we don't know if he says yes or no, because again, he has laid his heart out on that driveway and said what he wants, and now she's coming with a very different offer.

So, I'm not sure what he'll say, but yes, it was always this hard cut of her at the school play and looking at these children and her son who she adores, and it was so important that she's a great mom and she loves being a mom, but she also wants this other self and this other piece of her and the joy and cinematic nature of her running to that. And certainly conflicted and uncertain and all of that. But yeah, she gets her Don Draper moment, I guess is the way I'd put it.

Sex/Life is streaming now on Netflix.

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