When Sarah Treem first conceptualized the idea of Showtime’s “The Affair,” she wanted to explore four characters from different two perspectives, with the audience serving as a third point-of-view that would essentially find a midpoint of truth. Fast forward to Sunday’s fourth season premiere and not only have the number of viewpoints more than doubled, but there’s also a new L.A. landscape from which to tell an invigorated story.

As is set out in the return episode, Helen (Maura Tierney) and Noah (Dominic West) have moved following Vik’s (Omar Metwally) job offer, and they’re butting heads more than ever. Meanwhile, a flash-forward scene with Noah and Cole (Josh Jackson) indicates that someone is missing and that there have been a string of intense events leading up to that moment.

Ahead of the season premiere, Treem talks with Variety about how the production move rejuvenated the series creatively, whether diversity was a consideration in casting this season’s new characters, how the perspectives inform one another this year, and why she feels a fifth season should ultimately be the show’s last.

How did having a bigger break between seasons help with crafting the new season?

Personally I felt that I needed a break but that wasn’t the reason we took a break. There were a lot of reasons we needed a longer lead time in this fourth season. Some of them were scheduling, there was this move to Los Angeles. And then there was some Showtime scheduling afterwards — they decided to hold the show and put it on the air later; this show has been wrapped and the cuts have been done for a while. But it was interesting because I’d never had an experience where I actually had so much time to write and edit the show. We had a lot of months leading up to shooting season four, many more months than I’m used to. And then we had a lot of months to cut it, because it wasn’t going back on the air right away. It was nice. It was a pace of creative life that I could handle as opposed to the mad dash from beginning to end, which is how television usually feels.

What does moving part of the story to L.A. do creatively to the season?

It’s a fresh start in a lot of ways for the characters. Some of them had gotten into ruts in their lives because this traumatic thing had happened and sometimes with trauma it’s hard to get out of it. You can’t escape these thoughts and everything keeps coming back to the trauma. People don’t usually move in television because it’s hard to move a production, but people move in life a lot. So this thought of people taking a fresh start and moving somewhere else to get a different scene is common. Helen needed a fresh start, things got dark for her character last season. She’d been born and raised in New York, and there was so much baggage for her, so the idea of starting over would appeal to the character. So for the show, the idea of starting over in a new location gave us permission to blow up some ideas and see what else is possible while not necessarily feeling like we had to service the same story. And what we found in the characters is that a lot of their baggage comes with them. That’s a lot of what this season is about — where you go there you are. You can’t really outrun yourself; you have to face it eventually.

Logistically how did shooting in New York and L.A. work?

Part of the reason we needed more time to write was because we were shooting out of order. We shot everything in Montauk first. There’s a lot in Montauk that happens at the end, so we had to basically have the whole thing broken and written before we started. So it was a challenge. One of the nice things about being on a fourth season of a show is that people know the show and we work well together and the different departments can anticipate problems before they arrive. Even people like our script coordinator and our script supervisor — those jobs were huge this year just because we were shooting so much out of order. Those people had been with us for a long time so they could get ahead of stuff. There was no way we were going to be able to come back to Montauk because we had applied for the California tax credit so we could only shoot a certain amount there. Rodrigo Garcia, who directed two of the earlier episodes [402 and 404], also did the finale and so he had to shoot some of the finale in the beginning but he totally rolled with it. It was a big team effort. We really had to be on it, and we were at the end. We pulled it off, which I’m really impressed by.

Was diversity a mandate in your fourth season casting of the new characters at Noah’s school, Janelle Wilson (Sanaa Lathan) and Anton (Christopher Meyer)?

It was a self-imposed mandate. Showtime has been great and they don’t do mandates, but it was us as writers saying we would like to diversify the show a bit and not just make it about four white people. We were doing it in Noah’s story, we were also trying to lean in across the board to basically show all the characters coming up against their own blind spots. But part of where your blind spots lay are in your biases and your feelings that your worldview is the only worldview, which felt in keeping with the show. It didn’t feel like a stretch for the show to start looking at race relationships from a perspective and get them wrong… as we get a lot of stuff wrong in this show in terms of how other people feel. It felt organic and like the right place to go, although it was also a conscious choice, for sure.

What does it take for a character to earn getting a point-of-view on this show?

It’s a little bit of trial-and-error, to be honest. We introduced a new character and her point-of-view with Juliette [Irene Jacob] last season and people were not happy. I was surprised, because she was such a fascinating character. But people didn’t know her. That was a lesson learned. This season, the character that has a new perspective is definitely a character who has earned it. We don’t just create new perspectives for fun, we create them when we can’t tell the story without the perspective. That was true for Juliette — I wanted a new character’s perspective on Noah who didn’t have the baggage that Helen and Alison [Ruth Wilson] had on him. In this season the character that gets a POV, there’s no way to tell the story without showing his POV.

Does adding that POV give viewers another perspective on Helen?

Yes, and this is really fun, actually. So at this point we’ve met Helen in her own perspective, we’ve met her in Alison’s perspective, in Noah’s perspective and in Cole’s perspective briefly. So this is basically the fifth character we were asking Maura to play. It was a real challenge. Maura thought it was fun too and we all got excited, but we wondered what we haven’t done with this character yet. How do we change her enough that she becomes a new character one more time? A lot of it actually was a collaboration between her and I and the costume designer, Caroline Duncan. She’s really in the DNA of the show. So we came up with the look for Helen’s new character and that helped a lot, actually. It’s sort of a uniform. And then the character emerged out of the clothes.

Are you cognizant of evolving and developing each version of these characters as the show continues or do you focus on who they see themselves as first and foremost?

They do evolve in other people’s point-of-views. Noah and Alison have evolved a lot in each other’s point-of-views and they’re pretty different from how they originally met each other. Noah very much evolves in Helen’s point-of-view this year as well.

Does that development affect the inconsistencies viewers see when replaying a scene from another character’s perspective?

It’s basically scene-by-scene specific. Like this season we were dealing with a divorced couple who were basically estranged from each other. When they talk to each other they’re not particularly happy so they’re not great at communicating. And they don’t have a lot of information about the other person’s intention so their point-of-views are pretty far apart. There’s a mix-up that happens at the school that in my mind is a crimeless lack-of-communication; she wasn’t intending to keep him out of the school — she just didn’t realize he wasn’t going to get himself in. But from his perspective she’s been so hostile that obviously she would try to box him out. We’re just always trying to respond authentically to the circumstance and ask ourselves where are the characters at right now, how do they feel about each other and then it emerges from there.

You mentioned learning from the introduction of Juliette, but do you also pay attention to viewer response when it comes to the four leads and how polarizing they can be to some?

I know and I can’t keep up. I thought about it a lot in the beginning but I can’t keep up. The points of view of the audience on the characters are so divergent and there are people who hate Noah and then love him. Then there are people who love Alison and then hate her. Love Helen and then hate her. Almost everyone just loves Cole. You don’t usually get anybody hating Cole, that’s like the one consistent on this show. …The audience’s reaction to the show is consistent with the thematics of the show in general, which is that there’s no conclusive perspective. It seems to change given the viewer. When I was first coming up with the show I thought of that a lot, how the viewer was going to be like the third point in the triangle, the third participant in the affair and bring their own perspective and bias and history and trauma to the show and then have their own interpretation of events that was kind of filtered through their own lens. Different people would be watching the same scene and watch a different show. That was my grand idea in the beginning and to some extent it’s kind of proven true. At one point I was reading recaps in two different publications and they were so different. They were basically oppositional, episode-by-episode. That’s the show itself, I thought that was so interesting.

Other than adding another POV this season, were there any ways you wanted to experiment with the format or delivery?

I love the way we’re using the flash-forward this year, I believe it’s the most successful use of this particular framework that we’ve done so far because it really is an essential part of the characters’ journeys, psychologically, as opposed to it being just a time period where a different mystery is playing out. I guess we’ve done that in years past too but this call and response between the past and present I really like. It’s not new but we did it better than before. And actually we have one very experimental episode. We have one amazing episode that breaks form in this very interesting way that I’m really excited for the audience to see and to see their response. It’s just something we’ve never done before but I can’t quite say more than that. It’s definitely in our world but we’ve never done it before and it’s just really cool.

How do the flash-forward and present-day storyline converge this year — do they come together in the finale or do they intersect before that point?

They come together before the finale.

Do you still see a potential fifth season as the end point?

Yes. I don’t know that the number was important, but as a writer I feel there’s basically one more turn of this wheel. We would need one more season to basically bring these characters through an epic in their lives. To an end of an era and then to release them into an era in which we will not see on television. My feeling is just that the story isn’t quite over yet, but it also doesn’t have that far to go. There’s one more turn of the screw.

“The Affair” season 4 premieres June 17 at 9 p.m. on Showtime.