Warning: This article contains spoilers for the season finale of Long Bright River, “Atonement.”

A season full of twists and turns, mysteries, and devastating family drama has all been wrapped up in Long Bright River‘s finale — just maybe not with a perfect little bow on top.

To recap, the serial killer Mickey (Amanda Seyfried) searched for all season was none other than her new partner, Eddie Lafferty (Dash Mihok). Mickey confronts him at gunpoint, recording his confession as she does so, only for the other women and friends of his victims to show up and take justice into their own hands by killing him. Though Mickey apologizes to her old partner and lover, Truman (Nicholas Pinnock), for thinking he was the killer and pulling a gun on him, he wisely tells her they can’t come back from something like that and she leaves. We learn Mickey quit the police force after the whole ordeal, and is figuring out her future.

Turns out, Mickey’s sister Kacey (Ashleigh Cummings) was never missing, but was actually pregnant and alive and well, getting sober while living with the pair’s dad (who was also, in a surprise twist, alive). At the end of the finale, Mickey and her adopted son, Thomas (Callum Vinson) — who is really Kacey’s kid — are shown meeting up with Kacey and her new baby, clearly working on mending their relationships.

It’s not all totally fine and dandy, though. Though the killer got what was coming to him, it’s implied that the head of police, and maybe others, were involved in the corruption and cover up that enabled him to get away with what he did for so long, and they unfortunately have not — and may never — face the consequences.

Ahead, Entertainment Weekly catches up with showrunner Nikki Toscano about what changed from Liz Moore’s book of the same name in the process of adapting the series, how the show subverts the “cop as savior” and other genre tropes, and where Mickey, Kacey and the other characters go from here.

ENTERTAINMENT WEEKLY: Before we get to the finale, just in the series as a whole, what was the most important thing to change — or not change — from the book?

NIKKI TOSCANO: Liz [Moore] and I talked a lot about that, about in the translation from script to screen, things are inevitably going to change. Maybe not just the character’s actions, but the investigative turns of the series. When you’re translating 300 or 400 pages into eight hours of television, there’s inevitably going to be changes. I think one of the biggest challenges of adapting Long Bright River into a series was how internal the main character is in the book, and how we knew what was in her head because it was written in first person, not because she was saying what was on her mind. So the big question became, how do we get what is inside Mickey’s head out into the world? And the answer was in surrounding her with characters who did the talking for her, who sort of pulled it out of her and pressed her on not only everything she was saying, but more importantly, what she was not saying. That way Mickey didn’t have to be forthcoming and we could preserve the internal nature of the character. 

Was there one thing that you were most deliberate about changing?

I think the biggest thing that we changed was, I think a lot of times, particularly in murder mysteries, where everyone’s consistently guessing who the killer is and why the killer may have done it, I think that for us, it was one of the things that we changed was the killer’s motive, so that it was more reflective of what we were trying to say about the eight hours of television we were putting out there.

How involved or on board was Liz with those changes?

Liz was involved every step of the way. She was in the writer’s room with us. She and I co-wrote a bunch of the episodes. So she was involved in every step in translating it from book to screen and was very game to tell the most compelling story once we got it on its feet. She didn’t stay married to certain elements or things that were in the book if they were going to compromise how we were ultimately telling this story. So she was quite a big part of it. And I think that the biggest thing is that we spoke a lot about tropes in certain murder mysteries and how to stay away from those tropes. A lot of the changes that we made were about adapting her story to one that served as, like I said, a larger metaphor for the story that we were trying to tell, which was a victim empowerment story. This was very much a story of empowerment of women who had been largely discounted and found a way to not only find their voice, but take their power back. And that was a story that both Liz and I were very interested in telling.  One of the things that I love the most about Long Bright River, both the book and the series, is that it aims to deconstruct the cop as hero narrative. It also deconstructs the victim narrative as well. It’s sort of upending this traditional cop as savior narrative of most police shows, which begins with our protagonist. Mickey is flawed. She’s not the best cop, but her superpower is that she’s from the neighborhood and it’s her relationships there that inform her ability to investigate the crime.

How did you sort of prep the actors for the killer’s big reveal and his motives — was there any secrecy around that?

No. I mean, we shared the episode in advance, and I think that all of us were committed to keeping a tight lid on both the identity of the killer and the reason that person was killing. In the book, it was more random. So when we got into the series, we really aimed to sort of, like I said before, put a finer point on his motive, one that served as a metaphor for the whole series and spoke more specifically to the reason why we were telling this story. So I think that that was something that was a little bit kept under wraps and was something that was discovered when we finally shared the eighth episode with the cast.

What were you hoping to accomplish with the finale, and how important was it to not give everything a perfect Hollywood ending?

Well, I think that there’s a lot of different things. I think first and foremost, this idea of what it means to be a police officer. And I think that we can only pull this through the lens of our main character, but she is a person who believes that she has chosen right in her life and that her sister has chosen wrong. And what she comes to discover over the course of the series, is that she realizes that her sister did not have a choice. And so I think that there’s something interesting about addiction, about poverty and addiction, and how it can get its hooks into a person and never let go. I think that Mickey starts to confront her own complicity in participating as part of an organization where she turned a blind eye to what was happening in the neighborhood.

I think that this is a series not just about addiction, but it covers those who love people that are suffering from substance use disorder, and the way in which we can be hopeful in believing that they’re able to rise above it, but that it’s always sort of a question that’s hanging over us at all times. Will they be able to rise above it? And I think that at the end of Long Bright River, we’re hopeful that these two sisters can, but we’ll never know. 

To that end, where do you think these characters go from here?

I think that we leave Mickey and Kacey in a hopeful place, and the series starts out with the sisters largely estranged. And by the end of it, they’ve come back together. And I think that we sort of leave the audience with the hope that they will stay together, that Kacey stays clean and that they can all stay together as a family. I think that for Truman, unfortunately, I don’t think that they’re ever going to come back from what Mickey did to him, however misguided she was in that moment. I think that when she pulled a gun on him, it’s just not something that he’ll ever be able to personally come back from. And I think that Mickey and Kacey and G [their grandfather, played by John Doman] are together for the first real time in their life. I think that G and Mickey at the start of the season are largely estranged, and certainly G and Kacey are. But over the course of the season, as G contemplates his own legacy and he and Thomas become closer, some of the ice begins to thaw between Mickey and G. And I think that there’s something beautiful about the fact that while G was very tough on the girls, it was because they were a painful reminder of the daughter that he’d lost. And enough time at this point has gone by where he’s certainly still pained by the loss of his child, but with Thomas, there comes a new hope, and with Kacey’s new baby as well. 

This interview has been edited for length and clarity.

Long Bright River is now streaming on Peacock.

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