Fans of Shark Week just devoured their 2022 installment from July 24-30, hosted by Dwayne "The Rock" Johnson and full of celebrity guests. The human race knows more about outer space than their own oceans, which is why sea monsters are such easy villains to use in movies -- it's also why Shark Week continues to fascinate yet thrill viewers. Sea monsters play on that fear of the unknown, that somewhere deep with the blue and black waters of the ocean is something lurking, waiting to strike.

Movies have had plenty of sea monsters as antagonists dating all the way back to the 1950s, with movies such as The Beast From 20,000 Fathoms. Some are scarier than others, ranging from mutated animals to unknown creatures that rise from the depths to feed on humans.

Octalus - Deep Rising (1998)

Closeup of the Octalus from Deep Rising (1998)

As a whole, Deep Rising goes for a more action-packed horror movie with some comedic elements. The monster attacking the ship itself is where all the horror lies. It first appears to be a swarm of eel-like monsters, but it turns out that they all connect to the same monster known as the Octalus.

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It can use its tentacles to see as well as devour its prey. On top of that, the tentacles can each operate to digest their victims as well, as shown when the survivors cut open a tentacle to reveal a partially digested human.

Genetically Altered Makos - Deep Blue Sea (1999)

The second generation shark baring her teeth in Deep Blue Sea

There are Deep Blue Sea is pure nightmare fuel. But they aren't just sharks, they're highly intelligent creatures due to genetic modification and they are executing an act of revenge and escape plan.

Two are 26 feet long makos that stalk the flooded corridors of an underwater facility to purposefully kill the humans. The third is a 40-foot-long shark and the leader of the bunch, trying to escape into the ocean. These are sharks that can think and plot which, combined with their ferocity, means they aren't animals, but thinking monsters with agendas.

Asian Pacific Crocodile - Lake Placid (1999)

The Asian Crocodile - Lake Placid

This is a 30-foot-long Asian Pacific Crocodile that somehow swam into a saltwater lake in Maine and became absurdly territorial, picking off anything that gets in its way. This creature from Lake Placid Jaws is for sharks, making audiences afraid to go into the water.

Similar to that shark, this crocodile is not shown often, and usually through quick flashes and shadows, but each kill is gruesome and effectively handled. But unlike the shark in Jaws, this monster is able to come onto land and be just as deadly. Even when it's visible, it still brings the chills thanks to the creature effects by Stan Winston.

Gill-Man - Creature From The Black Lagoon (1954)

Creature from the black lagoon

This titular creature would go on to become one of the classic Universal monsters, alongside The Invisible Man. It was one of the first of its kind, able to bring horror from below by filming the monster under the water as it stalks the human characters.

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The monster suit itself holds up rather well; in certain shots, the Gill-Man is still a terrifying monster, especially when he's in the water. It's why the monster is still tributed in many films, shows, and even comics.

The Kraken - Pirates Of The Caribbean: Dead Man's Chest (2006)

Captain Jack Sparrow fights the Kraken

The the many iconic monsters that the heroes have to fight. One of the most famous is the tentacled terror of the Kraken, Davy Jones' personal pet that can bring down the most giant ships in seconds.

Whenever the Kraken attacks in Dead Man's Chest, it is treated as a genuine sea monster, as it decimates any ship and slaughters crew with its tentacles. It's also so massive that the audience can never quite tell what the full beast looks like other than the tentacles and its massive maw of teeth.

Gwoemul - The Host (2006)

The monster attacking in The Host.

Similar to Shin Godzilla, Gwoemul is the result of mutation from man's poor decisions. It is a fish that mutated to have legs and on a killing spree in South Korea. Already on its own, it is a deadly creature that kills and captures innocent civilians for food.

On top of that, the Gwoemul from The Host is also the source of a new and lethal virus strain. So even when this monster is not killing people directly, it's still causing a plague that kills hundreds.

Depladon - DeepStar Six (1989)

The Depladon rising out of the water in DeepStar Six

In the late '80s and early '90s, there were a lot of attempts to capitalize on the success of The Abyss with underwater horror. One of the more famous attempts was DeepStar Six, which introduced audiences to the Depladon, a massive crustacean unearthed by undersea explorers. Where most sea monsters are designed to be more fish-like or akin to sharks, the crustacean design was unique for the time.

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It acts similar to the Xenomorph from Alien by delivering plenty of gory kills and going back into hiding, waiting to strike. It seems to have an impeccable camouflaging ability since it can hide even in a small flooded room, as long as it's underwater. As a result, any time it appears, it's always a surprise and manages to be the highlight of DeepStar Six.

Clover - Cloverfield (2008)

Clover rampaging through the city in Cloverfield

This monster is a looming threat throughout one of the most famous found footage movies, but only has a few minutes of screentime. Most of the movie focuses on characters and how they deal with the destruction that the monster causes to New York City. That doesn't stop this strange sea monster from leaving an impression because not only is it difficult to describe but there is no explanation for it.

All that is ever hinted at is something falling from the sky to land in the ocean. Did this object create the monster or awaken it? It's up to the viewer. What is confirmed is that it is seemingly indestructible and Clover is only an infant. Accompanying the massive kaiju are small insect-like parasites that can kill in one bite. Viewers can't help but imagine what a whole family of Clovers could do to the world.

Cthulhu - Underwater (2020)

Closeup of Cthulhu's face in Underwater 2020

Smaller creatures that stalk humans on the ocean floor are scary enough, but Underwater has a startling twist. The creatures are all connected to a much bigger threat, which turns out to be none other than Cthulhu from H.P. Lovecraft's lore. What begins as a sci-fi horror under the sea in the same vein as Ridley Scott's Alien turns out to have some mystical undertones.

With just a few minutes on-screen, Cthulhu's presence brings a sense of malice that turns things from survival horror to a fight for planet Earth, as it's shown that Cthulhu was about to escape to the surface before being stopped by Kristen Stewart's Norah. Nothing about the god-like creature's history or Lovecraft's lore is explored, but that lack of understanding helps make Cthulhu even creepier.

Bruce - Jaws (1975)

Martin Brody facing off with Bruce The Shark in Jaws

It can be argued that the shark from Jaws is simply an animal, but Bruce is shown throughout to be far from a normal shark. Most sharks are actually docile and attack humans due to a case of mistaken identity. But Bruce attacks any chance he gets and not just to feed either since shark digestion is really slow.

Both Matt Hooper and Quint comment on how they've never encountered a shark that acted like this. Bruce even endured three air barrels and still managed to submerge. After that, he brought down an entire fishing boat, reducing the heroes to their worst state. He may not be some mutant or kaiju, but Bruce is definitely a monster in Jaws.

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