It took only two episodes for Sky’s explosive new six-part crime drama Under Salt Marsh to sink its claws deep into audiences — and they’re not letting go. Premiering on Sky Atlantic and NOW on January 30, 2026, this haunting Welsh noir has exploded with rave reactions, with fans declaring it “slow-burn television done right,” “beautifully shot,” and “brilliantly acted.” Viewers are confessing they’re instantly addicted, glued to their screens, unable to look away from the moody, unforgiving tension that creeps under your skin and refuses to release its grip.
At the heart of the obsession is Kelly Reilly — the powerhouse star of Yellowstone — delivering what many are calling her most devastating performance yet. As Jackie Ellis, a former detective now hiding behind the quiet life of a primary school teacher, Reilly is raw, magnetic, and utterly heartbreaking. Her Jackie is a woman bowed by grief and failure: three years earlier, the unsolved disappearance of her nine-year-old niece Nessa shattered her career, her family, and her trust in the world. Now, living in the fictional coastal town of Morfa Halen (Welsh for “Salt Marsh”), Jackie stumbles upon the lifeless body of one of her eight-year-old pupils, Cefin, apparently drowned in a drainage ditch amid the eerie, tide-swept marshes one stormy night.
The discovery isn’t just tragic — it’s a brutal echo of the past that Jackie thought she’d escaped. As a massive, once-in-a-generation storm brews offshore, threatening to wash away every trace of evidence, Jackie is thrust back into the darkness she fled. Forced to reunite with her estranged former police partner, Detective Eric Bull (played with quiet, simmering intensity by Rafe Spall of Trying and The English), the two must confront not only Cefin’s death but the lingering wounds of Nessa’s case — a failure that drove a wedge between them and cost Jackie everything.
The chemistry between Reilly and Spall is electric and fraught — immediate hostility crackles in every glance, every tense exchange, hinting at a history far more complicated and painful than a simple professional fallout. Their reunion isn’t partnership; it’s a collision of guilt, resentment, and unresolved trauma. As they dig deeper into Morfa Halen’s tight-knit community — where everyone knows everyone’s secrets, and the encroaching sea mirrors the rising tide of buried truths — the investigation unearths connections that fracture families and expose long-hidden horrors.
What sets Under Salt Marsh apart from the flood of crime dramas is its masterful slow-burn pacing. Creator, writer, and director Claire Oakley builds suspense not with cheap jump scares but with oppressive atmosphere: the relentless Welsh wind, the desolate marshes that swallow light and sound, the constant threat of the storm erasing clues before they can be uncovered. Cinematography is stunningly bleak — sweeping shots of fog-shrouded dunes, rain-lashed streets, and isolated homes perched precariously between mountains and sea — creating a sense of isolation and inevitability that feels suffocatingly real.
Early episodes introduce a stellar supporting cast that elevates every scene: Jonathan Pryce (The Crown, Slow Horses) as Cefin’s grieving grandfather Solomon Bevan, bringing gravitas and quiet devastation; Kimberley Nixon and Mark Stanley as Cefin’s shattered parents Shell and Danny, whose raw grief scenes deliver gut-punch after gut-punch; Harry Lawtey (Industry), Naomi Yang, Brian Gleeson, and others rounding out a community where suspicion festers like salt in a wound.
Viewers are losing sleep over it. Social media is flooded with reactions: “Gripped from minute one — this has Broadchurch vibes but darker, more personal,” one fan posted. Another raved, “Kelly Reilly is phenomenal; her pain feels so real you can’t look away.” Many compare it to the best of Scandi-noir or Welsh gems like Hinterland, praising the emotional depth, clever plotting, and how it teases out inevitable connections in a small town without ever feeling contrived.
But beware — this isn’t cozy viewing. The series dives headfirst into grief, guilt, and the psychological toll of failure, with twists that are brutal, unforgiving, and perfectly timed to keep you guessing. Just two episodes in, and fans are already begging for the weekly drops (new ones Fridays until the finale on February 27), admitting the moody Welsh backdrop, raw performances, and creeping dread have left them shaken, breathless, and desperate for more.
Under Salt Marsh isn’t just another crime thriller — it’s the kind that burrows into your mind, lingers in the shadows of your thoughts, and refuses to let go. In a sea of predictable procedurals, this is the one that truly creeps under your skin… and stays there.
