Josh Hartnett Faces off Against a Terrifying Sea Creature in First ‘Below’ Trailer

Netflix has built an entire subgenre around small, isolated communities facing threats they can’t fully explain, and the streamer’s latest thriller looks ready to join that lineup in dramatic fashion. This time, the danger isn’t lurking in the woods or hiding in plain sight; it’s coming straight from the ocean itself.

That threat forms the backbone of ‘Below‘, a new limited series that’s been quietly building buzz since its original announcement back in February 2025. With a first teaser now finally out in the world, fans are getting their clearest look yet at exactly what kind of story they’re in for.

The teaser introduces Calvin Penney, played by Josh Hartnett, a big-hearted but stubborn fisherman in a small Newfoundland town still haunted by his father’s mysterious death decades earlier. When an unidentified sea creature begins terrorizing his hometown, Calvin is forced to fight to hold his tight-knit community together, all while trying to keep his son Wade, played by ‘Stranger Things’ alum Charlie Heaton, safe from whatever’s lurking beneath the waves.

To confront the growing threat, Calvin teams up with Fonda, a visiting marine researcher played by Mackenzie Davis, as the two work together to uncover the island’s buried secrets before it’s too late. According to Netflix’s official synopsis, the six-part limited series blends local myth, suspense, and heartfelt humor while exploring themes of family, community, and inevitable change.

The series comes from creator Jesse McKeown, known for his work on ‘The Umbrella Academy’, who serves as showrunner and executive producer alongside Hartnett himself. Speaking to Tudum, Hartnett described being immediately drawn to the material, explaining that he read the first two scripts in under an hour and found the concept and character unlike anything he’d encountered before.

That authenticity extended well beyond the page. Hartnett and Heaton reportedly immersed themselves directly in Newfoundland culture to prepare for their roles, with Hartnett recalling to Tudum how spending time with locals over lobster and stories helped shape his understanding of the island’s history and people.

Heaton had a similarly hands-on experience while soaking up the regional atmosphere around St. John’s, Newfoundland’s capital. He told Tudum that Newfoundlanders have a distinct warmth toward visitors, recalling how his driver on the very first day offered to bring him supper later that evening, a small gesture that stuck with him throughout filming.

The supporting cast rounds out with Ruby Stokes, Kaleb Horn, Rohan Campbell, and Willow Kean, alongside Natasha Henstridge and Mary Walsh. Filming took place on location in St. John’s, Newfoundland, lending the series a grounded, authentic backdrop for its supernatural storyline.

For Heaton specifically, ‘Below’ marks just one of two major Netflix reunions on his upcoming slate, with the actor also set to star in the streamer’s upcoming ‘Peaky Blinders’ sequel series as one of two heirs to the Shelby name. That kind of packed schedule speaks to how in-demand Heaton has become since his breakout years on ‘Stranger Things’.

With its blend of small-town intimacy and creature-feature dread, ‘Below’ looks poised to tap into the same kind of tension that’s made ocean-set horror a reliable hook for decades. All six episodes are set to drop on Netflix on October 8.

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