Josh Hartnett faces a terrifying mystery from the deep in Netflix’s new thriller Below

Josh Hartnett has found a particularly interesting second act, and his latest role looks like another chance for the actor to have some fun. In Netflix’s new limited series Below, Hartnett plays a Newfoundland fisherman whose already troubled life is thrown into chaos when a mysterious force emerges from the sea.

The six-episode thriller arrives on Netflix on October 8, 2026, and the newly released full trailer offers a better look at the strange events unfolding in the isolated coastal community.

A strange iceberg brings an old nightmare back

Hartnett plays Calvin Penney, a fisherman living in a small Newfoundland town. He has spent years carrying the emotional weight of his father’s mysterious death, and that trauma comes rushing back when something deeply unsettling begins happening around the community.

The trailer hints that a huge iceberg appearing offshore is connected to the disturbances. Before long, the town is dealing with a threat that appears to come from beneath the water, while Calvin is forced to confront memories and secrets he would rather leave buried.

Netflix describes Calvin as a stubborn but big-hearted fisherman who is determined to protect his family and hold his close-knit community together. His son Wade Penney, played by Stranger Things star Charlie Heaton, becomes part of the growing danger.

The mystery also brings Fonda Howander, a visiting marine researcher played by Mackenzie Davis, into Calvin’s orbit. Together, they begin trying to understand what is happening beneath the surface and uncover the secrets surrounding the island.

Watch the official trailer

The trailer does a good job of establishing the mood without giving away exactly what is waiting in the water. There are glimpses of destruction, strange phenomena and frightened residents, but Netflix keeps the actual creature and the full nature of the threat relatively mysterious.

That restraint works in the show’s favor. Rather than explaining everything immediately, Below leaves enough unanswered questions to make the central mystery worth following.

Hartnett is at the center of it all

Hartnett has been enjoying a notable career resurgence in recent years, and his performance in M. Night Shyamalan’s 2024 film Trap was a particularly memorable example.

In Trap, Hartnett appeared to relish playing a character very different from the more restrained roles associated with parts of his earlier career. Below seems to give him another opportunity to lean into a character carrying considerable emotional baggage while dealing with an increasingly bizarre situation.

Calvin is more than a fisherman caught up in a monster story. He is a single father of three who is struggling to keep his fractured family together while dealing with tragedies that have followed him since childhood. Hartnett has described Calvin as someone who has come to feel cursed and disconnected from both his community and his place in the world.

That personal history should give the supernatural elements a stronger emotional foundation.

A Newfoundland setting adds to the atmosphere

Below was filmed in Newfoundland, Canada, using the region’s rugged coastline and distinctive landscape as the backdrop for the story.

The setting is an important part of the show’s identity. The isolated fishing community, cold waters and imposing landscapes give the series an appropriately uneasy atmosphere before the mysterious creature even enters the picture.

Netflix says the story combines local myth, suspense and humor with themes involving family, community and change. The series was created by Jesse McKeown, who also serves as showrunner, with Karen Walton, Perry Chafe and Natty Zavitz among the writers. Episodes were directed by Jamie Childs, Helen Shaver and Stephen Dunn.

The supporting cast includes Willow Kean as Ruth Penney, Ruby Stokes as Mary Penney, Rohan Campbell as Jay Penney and Kaleb Horn as Noah.

Netflix is keeping the mystery intact

One of the most promising things about the latest trailer is how little it actually explains.

We know that something is terrorizing the town. We know Calvin’s father’s death is somehow connected to the story. We know the arrival of the mysterious iceberg precedes a series of increasingly disturbing events. Beyond that, there is still plenty of room for the series to surprise viewers.

Netflix’s official synopsis describes the central threat as a mysterious sea creature, while the trailer suggests that Calvin and Fonda will have to go deeper into the mystery to discover what is really happening.

That makes Below an intriguing prospect for viewers who enjoy creature thrillers but would rather not have the monster completely explained before the first episode even begins.

All six episodes will be released on Netflix on October 8, 2026.

For Hartnett, it looks like another wonderfully strange role. For Netflix, Below could be a compelling blend of family drama, maritime mystery and creature horror, with Newfoundland itself providing much of the atmosphere.