Under Salt Marsh Blends Welsh Mystery With Climate Peril

The Welsh coast, with its windswept marshes and looming skies, has rarely felt as haunting or as urgent as it does in Under Salt Marsh, the new six-part crime drama that premiered on Sky Atlantic and NOW on January 30, 2026. Set in the fictional town of Morfa Halen, the series weaves together a deeply atmospheric murder mystery and the ever-present threat of climate change, drawing viewers into a world where the land itself seems as restless and troubled as its inhabitants.

The story begins with a tragedy that sends shockwaves through the tight-knit Morfa Halen community. Jackie Ellis, played with a raw, ghostly intensity by Kelly Reilly, is a former detective turned primary school teacher. Her life is upended when she discovers the body of Cefin, her eight-year-old pupil, lying in a drainage ditch on a rain-drenched evening. The discovery is especially harrowing for Jackie, not just because of her bond with the boy, but because it echoes the unsolved disappearance of her niece, Nessa, three years earlier—a case that ended Jackie’s police career and left her emotionally scarred. According to theartsdesk, "the fallout from the case triggered the end of her police career, and has evidently inflicted lasting emotional damage."

Jackie’s trauma is palpable, and as she moves through the sodden streets and marshes of Morfa Halen, it’s clear that the landscape itself mirrors her inner turmoil. Reilly’s portrayal, as described by inews.co.uk, is "translucent—skin whiter than linen, her hair a smudge of russet against the greens and greys of the coast—making her character seem spectral." Jackie is isolated, haunted by both the past and the present, and her only connection to the town seems to be through fleeting, secretive encounters and the weight of unresolved grief.

The investigation into Cefin’s death is led by Detective Eric Bull, portrayed by Rafe Spall. Bull’s arrival is anything but comforting. With a Birmingham accent that feels oddly out of place in the Welsh setting, Bull is abrasive, blunt, and seemingly devoid of empathy. As theartsdesk notes, "you could call him blunt or you might prefer bloody rude, and hifalutin’ concepts like empathy and concern have been erased from his repertoire, if they were ever there." The tension between Jackie and Bull is immediate and complex. They share a fraught history—once police partners, now estranged by betrayal and the unresolved pain of Nessa’s disappearance. Their reunion, forced by the new tragedy, is anything but harmonious. When they meet, they address each other by surname, a subtle signal of distance and unresolved issues. In the words of inews.co.uk, "They used to be police partners but it ended in unnamed betrayal and now one is set against the other despite their collective desire to solve the puzzle."

The supporting cast adds further depth and eccentricity to the unfolding mystery. Jonathan Pryce delivers a memorable performance as Solomon Bevan, Cefin’s grandfather and a local farmer who protests against the prospect of mass relocations due to rising tides—a nod to the real-world anxieties facing coastal communities. Pryce’s character, as described by theartsdesk, "gathers the locals on the beach and orates in a loud hellfire-preacher voice," embodying both the wisdom and the stubbornness of the town’s elders.

Other townsfolk, like the menacing Osian and the enigmatic Kieran Benbow—who lives in a shack on Spider Island and keeps bees—contribute to the drama’s sense of unease. The recurring motif of bee stings and the children’s drawings of a mysterious "bee man" in a spacesuit add layers of intrigue and symbolism, blurring the line between human threat and the inscrutable forces of nature.

Yet, the greatest menace facing Morfa Halen isn’t just the killer. The series is suffused with the looming threat of climate change. As a once-in-a-generation storm gathers at sea, threatening to flood the town and wash away crucial evidence, the environmental stakes become inseparable from the human drama. The threat of rising sea levels is not just a plot device but a reflection of real-life anxieties. The show was filmed in Fairbourne, a real Welsh village on the Mawddach Estuary, which, according to BBC reports cited by womanandhome.com, has been identified as "at high risk of future flooding due to climate change, and residents have been told it is beyond saving." The village could become uninhabitable by 2054, with plans to decommission it and return the land to marsh.

Other filming locations include Anglesey, Llanbedr, Menai Bridge, and Cardiff, each contributing to the show’s bleak and beautiful visual palette. The marshes, estuaries, and endless skies aren’t just scenery—they’re characters in their own right, pressing in on the town and its people with a sense of inevitability. As creator Claire Oakley told Radio Times, "It’s definitely the most remote place that I’ve filmed in, and it really seeps into you in a way that it must do for the people of Morfa Halen."

Kelly Reilly herself reflected on the resonance of the setting, saying, "It’s fictional but inspired by real rural communities in coastal towns across Wales, threatened by climate change and flooding. We filmed on location, which added authenticity. The environment reflects Jackie’s emotional state and the fragility of the community. Water is symbolic—rising tides, washed-away evidence, the feeling of helplessness. The environmental message is present but not preachy. It’s up to the audience to interpret, but it’s undeniably part of the story’s urgency."

The series has been praised for its atmospheric storytelling and visual style, drawing comparisons to Scandinavian crime dramas while maintaining a distinctly Welsh identity. The relentless rain, the grey skies, and the omnipresent marshes create a sense of oppression and melancholy, yet there’s a strange beauty in the desolation. As inews.co.uk observes, "Oakley gives the north Wales coast a similarly otherworldly look as she takes us down through the furrows and ditches dug out of the land by the elements, then up to the enormous skies hanging above endless, unforgiving marshland."

Beyond the central mystery, Under Salt Marsh is a meditation on loss—of loved ones, of community, and of land itself. The unresolved disappearance of Nessa, the death of Cefin, and the threat of the town’s extinction are all intertwined, each amplifying the sense of fragility that hangs over Morfa Halen. As the storm bears down and secrets begin to surface, Jackie and Bull must confront not only the mysteries of the present, but also the ghosts of their shared past.

Episodes of Under Salt Marsh air weekly on Fridays at 9pm on Sky Atlantic, with all episodes available to stream on NOW. The series stands as a gripping, evocative portrait of a community on the edge—where every clue, every tide, and every memory threatens to be swept away by forces beyond anyone’s control.