Things seemed so simple when The Affair first premiered on Showtime in 2014 — two married people telling their own versions of an illicit relationship. Five seasons later, things have become a lot more complicated, perhaps even at times bonkers; but the series finale, which aired this Sunday, is relatively sedate, focusing on key characters including Noah (Dominic West), Helen (Maura Tierney) and, 30 years in the future, grown-up Joanie (Anna Paquin) finding some degree of catharsis.

The Affair has always been a show about flawed people, and showrunner Sarah Treem has never been shy about acknowledging the some of the show’s flaws, while also never being afraid of celebrating its biggest swings. The finale, she says to Paste, doesn’t explain every last detail of what happens to these characters, like many series finales: “I think the thing about ending a show is that there will be story left untold. But you have to treat the finale like any other episode and figure out what needs to be told for this particular story to work. And then just trust that the audience has enough understanding of the characters that they can fill in the gaps.”

It’s up to the audience to decide what they think, ultimately, which means The Affair is ending just as it began — believing firmly that there is no such thing as objective truth, when it comes to our memories.

Below, Treem tells the story behind the finale song choice (including the Fiona Apple cover which plays over the final moments), digs into the eerie ways in which the show reflected real life events over the years, defends the choice to let a man get away with murder and also explores how the complicated nature of the narrative led to a “present day” narrative set years in the future.

She also doesn’t agree with my interpretation of certain elements of the finale. But that’s more than apt, given the nature of the show.

This interview has been condensed and edited for clarity.

Paste: When it comes to approaching a series finale, there’s always this really interesting question of deciding how much you want to reveal and explain, versus how much you want to leave unsaid. What was your your process in terms of kind of drawing those lines?

Sarah Treem:Do you feel like we left more unsaid or explained more?

Paste: I feel like there’s a lot you can kind of assume. Like, for example, it’s never explicitly said that Helen and the kids move back to Montauk, but there’s evidence that suggests as much. You probably could have gone a lot further, but it wasn’t like there was a shortage of details.

Treem: I guess I actually felt like we might have gone a little farther than I was comfortable with, that I would have done on another episode, because it was the finale. I did feel a certain pressure to explain certain things that I would have liked to have left unsaid just by virtue of my own storytelling sensibilities. In terms of Helen and Noah, that’s interesting that you think that they came back to Montauk. In my head, they didn’t. In my head, she came back later. But, yes, that was very deliberately left pretty open. You know, it’s never entirely clear do they get married again, do they not get married again — you know, what kind of relationship do they have in the future? They obviously had something. But we don’t say what it was. And I guess for me that felt like it doesn’t really matter. You know how they feel about each other, so you don’t need to know exactly what the day-to-day reality of their relationship was after the finale.

Paste: Now that I think about it, on the one hand, you say that you don’t necessarily think they got back together, but her name on the gravestone is Solloway. At the same time though, Noah’s not wearing a wedding ring. So we’re left with that up in the air.

Treem: Exactly, and Helen’s name goes back and forth this season. Like if you notice at one point she says call me Butler. But it’s never entirely clear whether or not she changed her name back to Butler. Or she’s asking people to call her Butler because she’s going back to her maiden name. So yes, again, that kind of ambiguity there is purposeful, like maybe she changed maybe they got remarried and she changed her name back to Solloway, maybe she just kept that name her whole life because that’s how that’s who she ultimately felt was her partner. Maybe it was an accident. We don’t really know.

One funny detail is that Maura [Tierney]—this is actually hilarious. A lot of things that I wrote on the show have ended up coming true in life—the climate change thing was pretty prescient. But it got to the point where it was getting a little ridiculous, and we were talking about it a lot. And Maura at one point, when we were talking about the end, she was like, “Don’t kill me. I don’t want you to kill me because I’m afraid of your witchiness. Don’t give me cancer, don’t kill me in a terrible way, just send her to a nunnery at the end.”

And I felt that I couldn’t do that, but I did very specifically, in homage to Maura, not make clear how Helen died. But we had been talking in the writers room about what Helen’s middle name would be, and someone said, well, why don’t we let Maura decide? And there was a moment on set where somebody came up to her and was like, What do you think Helen’s middle name is? And she’s like, I don’t know, why? And then that writer/producer went off and another producer came up later to ask, hey, have you thought about Helen’s middle name? And then she was like no, you know, and then that person left and then somebody else… At one point, it dawned on her why we were asking — she turned to the script coordinator and was like, “Are they trying to put that on a tombstone? Is that why they keep asking?”

Paste: When it comes to the “witchy” aspects of the show, Episode 10 of this season depicted a wildfire which destroys Topanga Canyon in Los Angeles — and right after it aired, a real-life fire did similar damage to the same region. What was your reaction when you woke up that Monday morning?

Treem: So I had been living in Mandeville, but just this summer I had moved, because my son is asthmatic. And I had been in Topanga before I was in Mandeville, so I have first-hand knowledge of Topanga Canyon. I know it well. But for the last couple of years we had been evacuated either from Topanga or Mandeville, and it was just getting to this point where I was like, I can’t deal with this anymore. I have to get my kid to a place where fires are not going to be seasonal. And so I woke up to all these texts on Monday morning from people who thought we were still in Mandeville and were worried—and then there was one text from from one of the writers this season [Donal Lardner Ward], and he just basically wrote “what hell have we wrought with the fire?”

The thing about that being prescient is that it wasn’t actually that prescient. I mean, the truth is, in the last three years I’ve evacuated from one canyon or another in California. October and November are fire season in Los Angeles. And you can count on there being a pretty massive wildfire and you can count on evacuations. So that’s the reality of the moment we’re living in, you know, whether or not people want to see it. That to me didn’t feel so much of a coincidence. I mean, it was a little bit of a coincidence that it happened that it literally broke out the day after the episode aired, but I do feel like it was just a matter of time.

Paste: You say “the moment we’re living in,” but this season it was confirmed that what we consider to be the present day on the show is approximately the year 2022 or 2024.

Treem: I know, I know.

Paste: At what point in the writers’ room did you guys start doing that math?

Treem: The reason that it goes forward is because we end up jumping time between seasons, but because we were putting dates on the gravestone pretty early on, the show starts contemporaneously with 2014. So we had rooted ourselves in the present when we started the show, and then we started jumping years. As you know, Season 2 actually takes place over the course of a couple years, and then Season 3 jumps forward three years and so we were jumping into the future.

We had this mandate for a while that we couldn’t show any dates. No dates on envelopes, no dates on license plates, because we were definitely getting into the future, but we didn’t really want that to be part of the conversation. That was fun for the art department.

But then, when we finally got to the reality of the final season we were like, okay, we’re going to have to we’re going to have tombstones, we’re going to be back in this graveyard—we’re gonna have to make some calls.

We actually made a critical mistake, where the date on Gabriel’s grave changes—in the pilot it’s a certain date, and then the next time you see it it’s actually a year later. The way that happened was like a really classic production mistake, where there’s a prop obviously which is Gabriel’s grave, and the prop had a certain date on it and then we made the choice that we wanted Gabriel to have died a little bit earlier, so we changed the date on the gravestone in post production for the pilot. And then when we came back and went back to the grave, we just used the prop again like you do, and I had forgotten that we changed the date on the pilot. And there were people who were like, “Wait a second. What just happened to the date that Gabriel died?” And it was to be totally honest a mistake.

Paste: A big choice the finale makes is that, essentially, the show ends with Ben getting away with Alison’s murder. At what point did this feel like the right decision?

Treem: So, that was the intention from the beginning. And the reason that was the intention is because this is not a show about people paying for their crimes. I mean, some characters have paid for other people’s crimes. But, you know, there’s been a lot of people who’ve gotten away with with things—including Helen, to be totally honest. And so it didn’t it felt like like the right ending would be for Joanie to kill Ben or bring Ben to justice. And that’s not what I think Joanie ultimately needed. The thing that’s that that’s holding Joanie back from happiness is not that Ben hasn’t been brought to justice, the thing that’s holding her back from happiness is that she can’t forgive her mother for what she thinks her mother did.

So what she needs to do is break the pattern, I think for us to really feel a sense of closure and happiness at the end of the story for her breaking the pattern would not be killing Ben. And it wouldn’t even be Ben being brought to justice. Breaking the pattern is basically going back to who her mother was at seeing her mother from a different perspective, understanding her mother’s story in a different way, and that releases her that from this trauma and this pain that she’s kind of put on herself. And that’s what allows her to go home.

I knew that for a significant part of our audience it was probably going to be really challenging, but it was right for the story that we are telling, which is not a story about crime and punishment. It’s a story about people learning and growing and forgiving each other and changing. That was a story that I felt wasn’t going to be solved with Ben getting caught.

Paste: You’ve got Dominic West and Catalina Sandino Moreno in old age makeup over the course of the season. Is there a reason that you decided to recast the older Ben, versus bringing back Ramon Rodriguez?

Treem: It was a scheduling conflict. But I think that Tony Plaña did a brilliant job. In some ways, I think that Joanie meeting a different Ben felt right, because she didn’t know him in the way that Alison knew him and he is a completely different person to her. For storytelling purposes, it was the right call.

Paste: The Waterboys’ “The Whole of the Moon” plays a massive role in the finale, both as the centerpiece of Noah’s flash mob surprise for Whitney as well as a cover performed by Fiona Apple for the final moments of the episode. What was the story behind its selection?

Treem: It was very exciting. I wanted a song for the dance in the finale, and I talked to my music supervisor and, and he suggested “The Whole of the Moon,” because I think I said I wanted a song about the moon — I can’t even remember why. But when I listened to it, I was like, “Oh my God, this one is perfect for our show.” Because it’s a song about people seeing things differently.

And then the Fiona thing was so interesting, because obviously she had recorded the opening theme song years ago: I had sent her this incredibly enthusiastic letter when I had written the pilot, and she’d read the pilot and loved it and sent the song.

I had never had any direct contact with her, but when we were coming to the final season, I had tried to get in touch with her again. But she changed managers, and she’s not the easiest person in the world to get in touch with. I just kept failing, and I was so disappointed.

And then she contacted us—kind of later in the game, Fiona Apple sent the music supervisor an email. She said that she’s just been loving the show, she was just incredibly enthusiastic and asked if she could be part of the final season. II said, Yes, please, whatever, you know, and I mentioned to her a couple of different songs that I’ve been thinking about for the end. And said, of course, if you want to do something original, please do that. She chose “The Whole of the Moon,” which was perfect, because that’s actually what I really wanted anyway. It just came together very organically.

Paste: How are you feeling about the way in which you ultimately got to include climate change into the final season — do you feel satisfied with how it all came together?

Treem: Yeah, for me, climate change was useful to us as a metaphor for everything in the show, which is that there are no relationships that will last if you don’t take care of them. You can’t take anything for granted. You can’t take your relationship with somebody else for granted, and we can’t take our relationship with the planet for granted.

What I like about the way that the show ends is that when we leave Noah on the bluffs and we start to pull back and back and back, we just basically keep pulling out until what you see at the very end is Montauk. And in some ways, it’s always been the primary character. You know, it’s been a show about these people, but it’s also been a show about this place. And just as the people change, the places changed. In the end, that felt right to me.

Liz Shannon Miller is a Los Angeles-based writer and editor, and has been talking about television on the Internet since the very beginnings of the Internet. She recently spent five years as TV Editor at Indiewire, and her work has also been published by The New York Times, Vulture, Variety, the AV Club, the Hollywood Reporter, IGN, The Verge, and Thought Catalog. She is also a produced playwright, a host of podcasts, and a repository of “X-Files” trivia. Follow her on Twitter at @lizlet.

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