The oceans encompass most of the planet, but explorers have only scratched the surface of what lies beneath. What lurks below in the murky depths of the sea has an innately unsettling quality. Stories of krakens hiding in ocean waters waiting to wreck passing ships, man-eating sharks poised to pounce on unsuspecting swimmers, and sirens luring sailors to Davy Jones’ locker are commonplace in history.

Many filmmakers have tried to appeal to our preternatural fears of the unknown, and some have been wildly successful in tapping into what’s so scary about the ocean. Sometimes they use a mythological beast to play on our phobias, and other times it’s just the force of nature itself – it’s clear that underwater movies about the ocean aren’t going anywhere. There’s no shortage of especially thrilling and scary ocean movies that dive into unexplored depths of this sub-genre. If you don’t already have thalassophobia, or an intense fear of the ocean, these best deep sea movies may change your mind.

20 ’47 Meters Down’ (2017)

Directed by Johannes Roberts

A vacation turned nightmarish is a surefire way to instill a fear of the deep blue sea. Starring Claire Holt and Mandy Moore, 47 Meters Down follows sisters Lisa (Moore) and Kate (Holt) as they decide on an adventurous whim to take a cage diving excursion offered by a group of locals they meet. When the sharks come too close for comfort, the pair begin ascending back to the surface but the boat’s towing cable snaps, sending the cage to the bottom of the ocean. The pair fight for survival with limited oxygen and the deadly predators circling.

It’s a formulaic shark thriller with an oceanic excursion gone wrong and two inexperienced protagonists against the sea’s most terrifying creatures. 47 Meters Down throws in a few twists and turns, but still doesn’t quite reach its full potential; however, it remains a solid installment in the genre that spawned a sequel, 47 Meters Down: Uncaged, that landed better with audiences. – Ali Teske

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19 ‘Sanctum’ (2011)

Directed by Alister Grierson

Nothing screams claustrophobia like the crushing black depths of unforgiving waters. The cinematography of the diving thriller Sanctum does just that. While mapping out and exploring one of the world’s most inaccessible cave systems, a team of scientists with varying levels of diving expertise must find their way back to the surface after a tropical storm floods the cave system, washing away their surface camp and any hope of help from the air. Audiences will recognize cinematic icon and deep-diving enthusiast James Cameron as executive producer.

While the film isn’t explicitly set in the open waters of the ocean, it’s a harrowing below-surface survival thriller that uses water as its monstrous villain. Where Sanctum succeeds is in its ability to provoke the audience to ask, “What would you do?” Its downfall lands with its character development; however, for those looking for a reason not to go into the water, Sanctum is a perfect excuse. – Ali Teske

18 ‘The Poseidon Adventure’ (1972)

Directed by Ronald Neame

It’s a new year of new oceanic fears for the characters aboard a luxury cruise. The Poseidon Adventure is a disaster thriller about the surviving passengers of an ocean liner that was capsized by a rogue wave on its voyage to Greece from New York City on New Year’s Eve. The survivors must band together to navigate the maze of ladders and clear corridors as the ship floods, burns, and grows more and more unstable. Gene Hackman Ernest Borgnine, and Shelley Winters are among the top-billed cast in the nine-time Oscar-nominated feature.

The Poseidon Adventure was the original film, long before Titanic, that made audiences question whether a cruise was a good idea. It’s also a psychological feature that uses the rising water line as a mirror for the rising tensions of the remaining passengers. A 2006 remake, Poseidon, keeps audiences on edge with certain claustrophobic scenes but fails to live up to the harrowing standard set by the original. – Ali Teske

17 ‘The Perfect Storm’ (2000)

Directed by Wolfgang Petersen

Based on the true story of the Andrea Gail’s crew tragically lost at sea, The Perfect Storm is a dramatic storm thriller with a star-studded cast. When three historic storms converge in the Northeast Atlantic, a Massachusetts commercial fishing boat battles the raging wind, rain, and waves on Halloween of 1991. Mark Wahlberg, George Clooney, John C. Reilly, and Diane Lane are among the cast of this Oscar-nominated feature. The Perfect Storm is a nonfiction novel written by Sebastian Junger recounting the infamous conditions the six-person crew encountered along with stories from their surviving loved ones.

The Perfect Storm is the feature film choice for audiences seeking something similar to the oceanic terrors and perils depicted in the TV series Deadliest Catch. Towering waves and relentless pounding rain are enough to invoke a fear of the water. This dramatic retelling of those fateful events is a stark reminder that the ocean’s unpredictability can be far more terrifying and shocking than any fictional creature feature. – Ali Teske

16 ‘Black Sea’ (2014)

Directed by Kevin Macdonald

Black Sea is a unique thriller in the genre with a diversified category of fear not typically depicted in modern oceanic features. In search of a sunken Nazi boat filled with gold, a former Naval officer (Jude Law) assembles and leads a crew of Russian and British soldiers to the depths of the Black Sea to recover the legendary U-Boat. This under-the-sonar thriller was a hit with critics but undersold to audiences.

Cold, dark, and crushing, the bottom of the ocean is the boogeyman of the genre for both the characters and the audience. It’s unexpected and terrifying versus the standard shark antagonist where there are clear boundaries and realistic expectations of inflicted fear. Black Sea while a submarine heist movie of sorts, is a psychological thriller that uses the inescapable depths of the ocean to press on the emotional and physical distress of those involved. It’s enough for any viewer to approach the sea with trepidation. – Ali Teske

15 ‘Sphere’ (1998)

Directed by Barry Levinson

Directed and produced by Barry Levinson, father to Euphoria’s Sam Levinson, and based on a novel by Michael Crichton, Sphere takes an A-list cast and puts them through a wringer. The film is more of a work of mind-bending science fiction than a conventional horror film. However, there are plenty of things to be afraid of, such as typhoons, jellyfish, and enormous squids.

While the film garnered mostly unfavorable reviews upon its initial release, it quickly gained a cult following thanks to its distinctive setting and an unsurprisingly charismatic Samuel L. Jackson. Sphere emphasizes the realization that humans just do not know what actually is happening miles below sea level.

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14 ‘Underwater’ (2020)

Directed by William Eubank

Few authors have been as successful in exploiting people’s fear of the unknown as H. P. Lovecraft. Underwater is a movie that plays on Lovecraft’s Cthulhu mythos, with their version of the Great Old One resting peacefully at the bottom of the ocean until his slumber gets disturbed, to horrifying results. Kristen Stewart gives a fantastic performance as a beleaguered mechanical engineer just trying to survive with a ragtag band of scientists.

One of the best ocean thriller movies, the film is extremely suspenseful, as it practically throws the protagonist into the fray as everything around her ignites and malfunctions. Despite featuring some of the scariest sequences in a horror film in recent years, Underwater was released in the dump month of January. Despite its financial failure, the film deserves to be viewed by and unnerve a larger audience.

13 ‘Open Water’ (2003)

Directed by Chris Kentis

Scuba diving is all fun and games until your boat leaves you behind in the middle of the ocean with no way to contact help. That is the disturbing premise of Open Water, which is made even more shocking because it is based on a true story. Things only get worse for the American couple stuck at sea as sharks surround them and exhaustion sets in.

People often have unpleasant ideas about what might occur if they get lost at sea. That Open Water was based on a tragic reality for a pair of divers makes this shark horror movie set at sea possibly the most frightening one. It effectively places the audience in the couple’s mindset as they experience the horrific reality of being at the whim of Mother Nature.

12 ‘Deep Rising’ (1998)

Directed by Stephen Sommers

As if contagious diseases, electricity going out, and running out of shrimp aren’t worrisome enough when you’re on a cruise ship, Deep Rising shows it could always be worse. The action horror film depicts skeevy mercenaries seizing control of a luxurious cruise liner just before a monstrous kraken threatens the vessel. The ensuing chaos results in plenty of carnage for the ship as the monster unleashes a few surprises.

The Mummy’s Stephen Sommers understands not to take things too seriously, and the ensemble appears to be having a good time with the B-Movie storyline. There are some genuinely terrifying sequences in Deep Rising, and the combination of physical and early CGI effects works brilliantly to produce some truly disturbing images.

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11 ‘The Reef’ (2010)

Directed by Andrew Traucki

The Reef is an Australian horror survival film about a group of friends whose boat starts to sink in the middle of the ocean as they’re being hunted by a great white shark. The gang sees an island off in the distance and must make the agonizing decision between staying with the doomed ship or swimming to shore.

It’s difficult not to be terrified of sharks, even though the actual harm they represent to swimmers is negligible. Still, The Reef knows that once you’re in the sharks’ territory, they’re in charge, and they’ve got razor-sharp teeth to prove it.

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10 ‘Triangle’ (2009)

Directed by Christopher Smith

Triangle shifts focus from monsters of the deep to the modern myth surrounding the Bermuda Triangle. Jess (Melissa George) meets up with her buddies for a lovely day out on the water until calamity strikes. Something traps Jess and her friends in a deadly temporal loop in the film, with no apparent way out.

A lively and tightly written story that both literally and metaphorically throws the audience for a loop propels Triangle. The best feature of the film is Melissa George’s outstanding performance, who really sinks her teeth into the brainy subject. This is among the best ocean horror movies that demand multiple viewings to really appreciate the puzzle pieces the writer and director layout.

9 ‘DeepStar Six’ (1989)

Directed by Sean S. Cunningham

Many of these flicks include giant sea monsters, and it’s easy to see why in DeepStar Six. In one of the best deep ocean movies, a group of military personnel and scientists band together to defend their undersea station from attacks by a massive sea scorpion. The combined power of a leviathan and the helplessness of being confined in water makes for interesting viewing.

DeepStar Six can be sluggish at first, but once it gets going, it pushes the pedal to the metal. The film does an excellent job of depicting individuals in heightened fight-or-flight mode in the face of a crisis that is beyond the regular confines of people’s understanding of nature.

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8 ‘Leviathan’ (1989)

Directed by George P. Cosmatos

Leviathan came out at the same time as several other underwater creature features, including Deep Star Six, and features a similar plot line about an attacking sea creature. The movie makes the case for its existence because of impressive practical effects by legendary special effects artist Stan Winston and underappreciated direction by George P. Cosmatos, father to Mandy‘s Panos Cosmatos. Leviathan creates a stressful atmosphere filled with watery nightmares that lurk within and outside the subterranean station.

Like John Carpenter’s The Thing, which came out around the same time, critics and audiences were too eager to dismiss the film, and it, too, needs to be revisited. The ensemble cast, led by RoboCop’s authoritative Peter Weller, does an excellent job of communicating the dreadful ramifications of their situation.

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7 ‘The Cave’ (2005)

Directed by Bruce Hunt

The Cave pushes the boundaries of thrill-seeking as a team of divers led by two brothers explore an underwater cave teeming with secrets. The movie had the unfortunate timing of releasing at the same time as The Descent, with both featuring beastly creatures attacking a group of underground explorers.

Despite a somewhat formulaic plot, The Cave does a terrific job in its own right, with stunning creature visuals that evoke fright. Several sleekly directed scenes, including a pulse-pounding cliff sequence, will make you never want to cave dive.

6 ‘Cold Skin’ (2017)

Directed by Xavier Gens

Although Cold Skin takes place above ground, it does an excellent job of exposing oceanic terrors. An unnamed man (David Oakes) travels to a remote island to work as a weather watcher, but gradually learns of the island’s terrifying truth. He eventually joins forces with a lighthouse keeper to repel assaults from beings emerging from the sea.

The film is very stressful and claustrophobic, particularly when the men are confined inside the lighthouse. The enigmatic creatures of Cold Skin can be both horrifying and sympathetic, but they mostly likely inspire viewers to never accept jobs in remote islands.

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5 ‘Adrift’ (2018)

Directed by Baltasar Kormákur

Adrift is categorized as a survival drama rather than a horror or thriller film, but despite the absence of action, it has thrilling aspects that can keep the audience’s attention. Directed by Baltasar Kormákur, the film is based on the actual account of a couple (played by Shailene Woodley and Sam Claflin) who set out on an ocean trip only to be slammed by a big hurricane, leaving them trapped in the middle of the sea with no means of contact, navigation or supplies.

Adrift‘s suspense comes from the protagonists’ fight to survive in the face of a huge storm and their subsequent struggle while stuck at sea. The realistic depiction of the deadly storm inspires a sense of horror and unease, reminding audiences of the awe-inspiring power of the planet.

4 ‘The Meg’ (2018)

Directed by Jon Turteltaub

The Meg is a sci-fi action film about a deep-sea vessel that is attacked by a giant shark that was thought to be extinct. Directed by Jon Turteltaub, the plot follows a group of scientists as they attempt to stop the titular shark before it does more harm.

While some may criticize its CGI and plot holes, its wild action sequences and entertainment value more than make up for its cheesier aspects. The Meg embraces its B-movie approach and has an undeniable ability to generate tension and a sense of danger. This is especially evident in scenes where the shark, a giant ancient predator, attacks and hunts the protagonists, who are completely vulnerable underwater.

3 ‘All Is Lost’ (2013)

Directed by J. C. Chandor

Director J.C. Chandor‘s All Is Lost is a survival drama film about a man (masterfully played by Robert Redford) who finds himself alone aboard a sailboat in the middle of the Indian Ocean after colliding with a shipping container and starts taking on water. The movie follows the challenges he encounters as he battles the elements and attempts to fix his boat.

All Is Lost is largely about man vs nature, with little dialogue and no flashbacks. The thrilling parts in the survival drama come from the man’s efforts to survive against the worsening conditions and the damage to his boat. Redford does an incredible job of portraying the struggles of isolation against someone as terrifying as the ocean.

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2 ‘The Shallows’ (2016)

Directed by Jaume Collet-Serra

The Shallows, directed by Jaume Collet-Serra, is a survival horror film about a surfer called Nancy (Blake Lively) who becomes trapped on a rock 200 yards from shore as a great white shark circles the limited area between her and safety. The film follows her as she attempts to escape and return to shore.

The Shallows does a phenomenal job of generating a stressful and tense environment. The protagonist’s fight to survive while stuck on a rock with a predator watching her results in some terrifying moments. Lively’s convincing acting is the true star of the movie, which deserves more attention in the niche genre.

1 ‘Jaws’ (1975)

Directed by Steven Spielberg

Jaws is a classic thriller that needs no introduction. Directed by Steven Spielberg based on Peter Benchley‘s eponymous 1974 novel, the movie follows the police chief of Amity Island, a fictional New England summer resort town, as he tries to defend beachgoers from a great white shark that has been attacking and murdering people.

Widely considered one of the most influential films ever made, Jaws is often credited for the bad reputation great white sharks still have today. It also became the pioneer of the summer blockbuster, thanks to brilliant marketing tactics and its innovative cinematic techniques. No one will soon forget its legendary theme, which likely still inspires a feeling of dread in anyone who hears it.

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