"An unthinkable crime”: Happy Valley and Slow Horses stars unite for a “spine-tingling" drama Under Salt Marsh

There are two shows that can do no wrong in our book – Happy Valley and Slow Horses – and if you feel the same way, you’ll be pleased to hear the shows’ stars are uniting for what has to be the ultimate crime series! Under Salt Marsh is Sky’s spine-tingling new thriller with an unthinkable crime at the heart of it – and it’s coming to our screens imminently.

The drama takes place in the fictional Welsh town of Morfa Halen, where the body of former detective turned teacher Jackie Ellis (Kelly Reilly)'s 8-year-old pupil, Cefin, is found, seemingly drowned. This isn’t, it transpires, the first time a traumatic occurrence has taken place in the town, with Jackie's niece, Nessa, having disappeared three years earlier. The question is, are the two cases linked?

With Happy Valley’s Mark Stanley and Slow Horses’ Jonathan Pryce among the cast, we’re expecting big things! Ahead of the show's arrival on our screens, here’s everything you need to know, including the cast, plot and how you can watch it.

What is Under Salt Marsh about?

Set in the fictional Welsh town of Morfa Halen, the six-part series introduces us to a tight-knit community, which is precariously nestled between towering mountains and a fast-encroaching sea that threatens its very existence. As a mammoth, once-in-a-generation storm begins to gather far out at sea, former detective turned teacher Jackie Ellis (Kelly Reilly) discovers the body of her 8-year-old pupil, Cefin, who appears to have drowned.

The discovery sends shockwaves through the community, but it also revives the ghost of an unsolved cold case that rocked the town three years earlier: the disappearance of Jackie’s niece, Nessa, which cost her career. Cefin's death summons Jackie's former partner, Detective Eric Bull, back to Morfa Halen to lead the investigation into a community he failed once before.

According to the official synopsis, “Convinced the cases are linked, Jackie and Bull must reconcile and race to uncover long-buried secrets inside Morfa, before the storm breaks and all the evidence is gone for good. An intimate and cinematic story, Under Salt Marsh takes audiences into the heart of a community bound by nature and fractured by an unthinkable crime.”

Writer, creator and showrunner, Claire Oakley, has described the series as "a crime thriller set in a community deeply connected to its environment, and interwoven with the heartache, fears, dreams and secrets of its people."

She says, "At the heart of it all is Jackie, a character who embodies the wildness of the place we're depicting. She's free-spirited, compassionate, and determined, with a steely resolve that makes her truly of the land. We're absolutely thrilled to have Kelly Reilly bringing Jackie to life."

Meghan Lyvers, Director of Original Series, Sky Studios UK&I, says: "Under Salt Marsh is a uniquely powerful drama which we are incredibly proud to support at Sky Studios. Claire Oakley is an exceptional creative talent who has crafted a deeply emotional and universal story which explores themes of loss, resilience, and community, all whilst pushing the boundaries of the crime thriller genre."

Who's starring in Under Salt Marsh?

The cast of Under Salt Marsh includes:

• Rafe Spall (The English, Jurassic World: Fallen Kingdom)
• Kelly Reilly (Yellowstone, Here)
• Jonathan Pryce (The Crown, Slow Horses)
• Naomi Yang (Nightsleeper, Wolfe)
• Harry Lawtey (Industry, Joker Folie à Deux)
• Dinita Gohil (Sandman, Greed)
• Brian Gleeson (Bad Sisters, Phantom Thread)
• Kimberley Nixon (Fresh Meat, Life and Death in the Warehouse)
• Mark Stanley (Happy Valley, The Reckoning)
• Dino Fetscher (Fool Me Once, Foundation)
• Lizzie Annis (The Witcher: Blood Origin, Extraordinary)
• Rhodri Meilir (Pren Ar y Bryn/Tree On A Hill, Craith/Hidden)
• Julian Lewis Jones (House of the Dragon, Wheel of Time)

How can I watch Under Salt Marsh?

Under Salt Marsh will be available to watch on Sky and streaming service NOW. Sky hasn't yet shared a release date for the series, but we do know it will be released at some point soon. As soon as we have a confirmed date, we'll share it here.