Scientists say that we know far more about space than we do our own oceans. That fact alone is scarier than most horror films today. Luckily, there's an entire subgenre dedicated to the horrors of the depths of the ocean.

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With the recent release of Underwater, everyone's fear of what lies beneath the sea is utilized to full effect. This Alien inspired one-off film starring Kristen Stewart is a perfect blend of humor and sci-fi underwater horror. In honor of its release, let's take a look back at some of the scariest marine monsters of movie history.

Siren from The Lighthouse

Robert Egger's isn't known to be much of a creature feature director by any means. The two-time indie horror mastermind is far more concerned with unnerving you than scaring you with rubber monsters. Because of this, his take on ocean-based terrors is linked directly with Freudian sexual psychology.

In his sophomore outing, Eggers tackled the black and white nightmare of The Lighthouse. Within it, there is a small sequence featuring a mermaid with some large anatomy. This monster itself is less the scare and more supported by incredible acting, sound design, and editing.

Davy Jones and His Crew

Some of the best monster designs are ones that are never actually in horror films. There is certainly an argument to be made that half of the monsters in fantasy and sci-fi films would fit right into a creature feature horror film.

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A great example is the crew of the Flying Dutchman in the Pirates of the Caribbean franchise. Lead by the tentacled Davey Jones, this undead crew has been reclaimed by the sea, contorting into the forms of various fish, coral, and shellfish. Their sheer presence is enough to imprint on the minds of all the young Disney fans who saw this series.

Pacific Rim Kaiju

Kaiju might be the best example of aquatic horrors. They tap into a worldwide fascination with the seas, and what huge titan-like beings might reside within. You can see them as a direct result of the horrors of Japanese myth and Lovecraftian fiction.

Guillermo del Toro's fandom of these beasts and their origins is no secret. So their presence in his sci-fi epic Pacific Rim can't go unignored. The sheer size of these monsters is fantastic, seeing them topple buildings and take on gigantic robots of the same size. The best part of del Toro's film is the diversity in design, giving each Kaiju a specific set of physical traits.

Cthulhu

Underwater Giant Teeth Poster

Underwater implemented a lot of ideas from other stories and films. So much of it feels like an homage to the original Alien, from the set and costume design to the opening titles. One inspired element though, came directly from the mind of H. P. Lovecraft, giving fans of his work one of the best interpretations of his most famous monster.

After the surviving crew reaches the drill near the end of the film, it is revealed that the human-sized monsters are nothing more than parasites to a larger threat: Cthulu. This god from the ocean deep rises from his slumber, ready to lash out on those who would steal from his domain.

The Kraken

The Kraken is one of those archetypal monsters that have been around since before films even existed. If anything represents the horrors of the deep better, we're unaware of it. Since the early days of humanity, some version of this tentacled titan held its legs around the imaginations of storytellers.

Because of this, The Kraken has appeared in numerous films, novels, and books. YOu can look as far back as the classic 20,000 Leagues Under the Sea or Clash of the Titans, or as recently as Pirates of the Caribbean to find this monster. There's just something about this giant squid we can't get enough of.

Alligators from Crawl

Perhaps these creatures don't come from the sea, but their terrors are just as water-based as any other sea monster. This sleeper-hit horrified and entertained just about everyone who saw it. Based in Florida, during a monster hurricane, a young woman tries to escape her flooding home with her injured father. Standing (floating?) in her way are hoards of ferocious alligators.

As some of the best aquatic horror, there's no sci-fi or supernatural element at play here. This film is simply humans against the forces of nature. Sometimes, that's scarier than anything hiding in deep ocean trenches.

Ghosts from The Fog

Aquatic horror is often more concerned with the terror of beasts than humans. But with The Fog, John Carpenter combined classic supernatural horror with oceanside terror. Set in an idyllic seaside community, The Fog is full of maritime nightmares.

A hundred years after a crew of sailors perished, their spirits return to destroy the descendants of the men who condemned them to their fate. The staging of these ghostly seamen is perfect. If John Carpenter knows anything, it's how to create an imposing horror silhouette. Although campy, it is an excellent time capsule of a horror film.

Creature From The Black Lagoon

The legacy of the Universal Monster universe is more one of gothic horror, utilizing the fears of the old world. Vampires, werewolves, and the undead ran rampant during this era. But, the final film to be considered part of this movement took a sharp detour from this legacy.

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Creature from the Black Lagoon is more like the science fiction terrors that would come during the 1950s. Universal created one of the most beloved movie monsters through this film. There are few as impactful as the Creature, with his signature fish-like design that has inspired the likes of Guillermo del Toro.

Godzilla

While the Kraken might be eternally classic, there are few other sea monsters and Kaiju that have had quite the impact as this king Titan. Godzilla has been beloved and feared for generations, holding his own among new franchises for decades.

This enormous monster from the depths of the oceans stands larger than nearly any other movie monster, sparking debates about the fairness of his upcoming battle with King Kong. No matter the outcome of that battle, we know that Godzilla will at least have the lasting power and interest of fans.

Bruce The Shark

While he might not have size on his side when compared to the likes of Godzilla, Bruce the Shark has prestige and simplicity on his side. Writers and storytellers can conjure up as many imaginary horrors that they want, but nothing is scarier than what really exists.

Sharks remain some of the most feared creatures on the planet thanks to this film. While the chances are still low on you ever running into one, that doesn't mean it could never happen. Stay afraid all you want of ghost pirates and giant monsters, we'll stay out of the water thanks to this giant shark alone.

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