How Liz Moore’s Novel “Long Bright River” Became a TV Series Starring Amanda Seyfried (Exclusive)

Liz Moore jokes that she knew Amanda Seyfried had to star in the TV adaptation of her novel, Long Bright River, when she saw a photo of the actress wearing a Philadelphia Phillies hat.

“I remember screenshotting it, texting it to [executive producer] Pavun [Shetty] and [showrunner] Nikki [Toscano] and being like, ‘She has to play Mickey Fitzpatrick,’” the author tells PEOPLE.

It was a moment close to home for Moore, who lives in Philadelphia, as well as Seyfried, who grew up in nearby Allentown, Pa. In Long Bright River, now streaming on Peacock, Seyfried plays Mickey, a police officer who works in the Philadelphia neighborhood of Kensington at the height of the opioid crisis. When three girls turn up dead, Mickey takes on the case, while also searching for her missing sister, Kacey (Ashleigh Cummings).

Long Bright River was published by Riverhead Books in 2020, but the novel was first optioned for television two years before it hit shelves. Moore, who also wrote the 2024 bestseller The God of the Woods, noted early interest from producers; she was eventually paired with Toscano to both co-create and co-write the TV series.

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“Things take a really long time to get made, as it turns out,” Moore says, of the adaptation process. “There's many twists and turns, and ups and downs. But that was a surreal moment for sure. And when Amanda came on board, that was also when things felt really real.”

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For Seyfried, who also serves as an executive producer on the series, bringing Mickey to life was an opportunity that she couldn’t pass up.

“I've always wanted to play a cop,” she says. “It's like a childhood dream to play somebody that I just was always in awe of, even though it's funny [because] I'm not good with authority.” She was also drawn to Mickey’s flawed character, which was particularly appealing from an actor's perspective.

“I loved the idea that there was this woman who didn't seem like she would be well-suited to be a cop, but was a cop anyway,” Seyfried says. ”This is a girl that has got a lot of issues, a lot of traumas. She's a cop, she's a single mother and she has all these responsibilities. It just seemed like it was chaos for her.”

“It's attractive to me to have a lot of balls in the air as a character…very specific parameters are really fun because it's like a puzzle,” she adds. "I like studying things and I just love going into worlds that I don't know. For me, it's the journey…I need to make sure that I'm not going to get bored while I'm away from my kids.”

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Changes always need to be made when adapting books for the screen, and Moore's book was no exception. She adjusted Mickey’s first-person perspective ("we did not want to use voiceover") and aged up Mickey’s son Thomas (Callum Vinson), to highlight how Mickey “adultifies him.”

The author also wanted to portray the police force's reputation and interaction with a community in the throes of the opioid crisis. Mickey’s flaws impact how she navigates her job too.

“She's part of this system and she's part of a neighborhood where the police are perceived with a lot of suspicion by the community, rightfully, because some members of the police force have done harm within the community,” Moore explains. “[Mickey] is constantly navigating her dedication to her job, her attempt to do her job to the best of her ability with honor, with dignity, while also being surrounded by police officers who aren't necessarily doing that work the same way.”

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Moore has a personal connection to Kensington, where she has worked with the community for over a decade. Her team cast local actors, and hired a leader from the Savage Sisters Recovery organization to work with talent to explain the effects of addiction and how to administer aid. As a tribute to Philadelphia, they also brought on local graffiti artists to tag the interior and exterior sets.

“It was really important to collaborate with the neighborhood of Kensington and the city of Philadelphia as we made this,” Moore says. “I don't think we would've done it without their voices being included.” It was also crucial to portray addiction as a medical problem, Moore says, as opposed to moralizing the condition.

“We were all aligned in treating people with addiction and their loved ones with dignity and respect and compassion,” she says.

”There was just so much care in telling the story in the right way," Seyfried says. "We can see ourselves in each of these people, and that's the point of storytelling, is to share and relate."

As such, both Moore and Seyfried hope audiences will be able to connect with the show — and stay locked in for all the twists it has to offer too.

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“A lot of people, unfortunately, can relate to either experiencing addiction themselves or being the loved one of somebody with substance use disorder. So I think a lot of people will connect to it on that level,” Moore says. “But also, it tells a really good, propulsive story … both the crime drama and the family drama are given equal opportunity to be surprising.”

“The crime drama aspect is so realistic and terrifying,” Seyfried adds. “But there's still that puzzle that we all love about crime dramas, and we get to try to figure it out together.”

Long Bright River is now streaming on Peacock.

Read the original article on People