Under Salt Marsh's Jonathan Pryce explains why thriller is "much deeper" than your average murder mystery

When the body of a nine-year-old boy is found in a drainage ditch in the remote Welsh town of Morfa Halen, the community is rocked by the harrowing possibility that there's more to Cefin's death than a horrible accident – and that one of their own is probably responsible.

And it's a feeling they know all too well following the disappearance of another child, Nessa, who went missing three years ago, the details of which remain unknown.

Yet, while Sky Atlantic's Under Salt Marsh is a murder mystery, Jonathan Pryce (The Two Popes, The Crown) who plays Cefin's grandfather Solomon, the patriarch of a local farming family, believes it goes beyond what we anticipate from crime thrillers on the whole.

"It's weird, I didn't feel like I was reading a murder mystery. I felt I was reading about a community that was under threat from the environment," he told RadioTimes.com, referencing the once-in-a-generation-storm that's rapidly heading towards the town, putting the investigation, headed up by Detective Eric Bull (Trying's Rafe Spall), at serious risk.

"But also, [there's] this ongoing unrest within the community because some of the murders are historical, and the community is already split, and then rent asunder again," added Pryce. "So it's a much deeper story than an obvious murder mystery."

Another feather in its cap, according to Pryce, is "the reveal of the murderer... is not straightforward".

"I think that's a very good, strong feature of the script. There are no obvious culprits for a long time, and I found that interesting."

Starring alongside Pryce and Spall is Yellowstone's Kelly Reilly, who plays detective turned teacher Jackie Ellis, who finds Cefin's body, and is also Nessa's aunt – a case which ultimately cost her her job and her friendship with Bull.

"These two characters have so much history, they've gone through something deeply traumatic together," Reilly said of that central dynamic."And I think Jackie, quite honestly, would love to never see him again because it's just too painful. She's not ready to."

"He's probably the worst person she could see in this moment because it just brings back all of the trauma of this case that they didn't solve together," she continued.

"And so him suddenly showing up at her house after finding the body of this child is like a horror film."

That detail was the "most attractive aspect" for Spall, who described their relationship – or lack thereof when we first meet them – as "unconventional".

"There isn't that risk of them getting together, but they've got a lot to work out," he expanded.

"They have a lot of love for each other and a lot of anger, and as we know there's a very fine line between those two emotions. It makes for a pretty original central duo."

Read more:

• Where was Under Salt Marsh filmed?
• Who's in the cast of Under Salt Marsh?
• Under Salt Marsh review: Flood-stricken crime drama continues the rise of Welsh noir

The first two episodes of Under Salt Marsh will premiere on Sky Atlantic and NOW on January 30th with a new episode following the next four Fridays.

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