[INAUDIBLE] Release the kraken.

Yes.

Release the kraken.

Recognizable by its massive size and tentacled limbs, the kraken is one of the most legendary and feared sea monsters of the deep.

Stories of the kraken say it could take down whole ships, grab sailors off decks, and create whirlpools, all to get humans into the water and into the monsters waiting beak, because despite having more than half the world's species choose from for dinner, apparently there is nothing in the ocean more delicious than humans.

I'm Dr. Emily Zarka, and this is "Monstrum."

We know less about the oceans on our own planet than we do about our solar system.

And before we started going to space, sailing far away from land was just about the scariest, most uncertain trip a person could take.

So much about the ocean is inherently terrifying.

It's dark, vast, deep, and unpredictable.

It sparks our imaginations of what could lie beyond the horizon or what lurks beneath the waves.

And that's where the Kraken comes in.

Release the kraken.

DR. EMILY ZARKA (VOICOVER): The first written mention of the colossal sea beast was by King Sverre of Norway in 1180. he tells sailors to look out for a large squid-like monster that swims the coast of Norway, Greenland, and Iceland.

Since then, the Kraken has continuously appeared in literature, most famously in the works of Jules Verne, Victor Hugo, and Alfred Tennyson.

It's not surprising that we first find this creature in northern Europe, given the reliance the Nordic people had on the ocean for trade, travel, and survival.

Unlike other sea monsters that require a bit more imagination, the idea of a giant tentacled creature prowling below the surface of the water, waiting to take down unsuspecting ships and sailors makes sense.

Because there are living organisms that fit the description, minus the sailor eating part.

The giant squid and the colossal squid are two living cephalopods that can be found in every ocean on Earth.

Giant squid really are giant, measuring up to 43 feet in length.

But the colossal squid holds the title of the world's largest living invertebrate, growing up to 49 feet long at current record.

The largest one found so far weighed over 1,000 pounds.

Oh, and in addition to suckers, it has barbed hooks on its tentacles.

And they are very fast swimmers.

Both species frequent the deep, cold waters of the ocean, making it hard to see them in their natural habitat.

Before the 21st century, no photographic evidence of a living giant squid existed.

It wasn't until 2006 that we first caught these creatures alive on video.

The kraken is bigger than giant and larger than colossal.

It's a sea beast with multiple tentacles that often acts aggressively towards humans.

A kraken is basically an angrier, much larger version of a squid.

Personally, I'm terrified of the kraken.

Something about those giant eyes, wiggling tentacles, and suckers just completely freaks me out.

And I'm not the only one.

Victor Hugo apparently hated anything with tentacles.

In his 1866 novel "The Toilers of the Sea," a character has a frightening encounter with an octopus who wraps itself around his body and almost kills him.

Hugo dedicates an entire chapter outside of the plot to rant about how terrifying and monstrous these, quote, "devil fish," are, writing about, quote, "what ancient legends call the krakens," he describes them as "glutinous masses endowed with a malignant will."

Hugo describes how such a creature could wrap itself around a swimmer and drown them and even goes as far as to say that they are capable of sucking blood with their tentacles.

He summarizes his fear of suckers stating, quote, "claws are harmless compared with the horrible action of these natural cupping glasses.

The talent of the wildebeest enter into your flesh, but with a cephalopod, it is you who enter into the creature."

Yikes.

There are real accounts of octopuses attacking and even drowning swimmers, many of which occur in the 19th century, the same time Hugo, Tennyson, and Verne wrote their kraken stories.

In Verne's "20,000 Leagues Under the Sea," Captain Nemo and his crew are attacked by not just one but 10 or 12 horrible monsters described as giant octopuses.

It's a bloody, inky, chaotic fight scene with tentacles flailing everywhere and the crew defending itself with hatchets and harpoons.

Tennyson's 1862 poem "The Kraken" depicts the monster as an apocalyptic force that will arise from, quote, "his ancient, dreamless, uninvaded sleep one day to be seen by men and angels."

The kraken appears in non-fiction literature as well with reports of giant squid corpses beginning in the 14th century.

We have accounts of massive tentacles washing ashore and of giant squid corpses floating at sea.

Sperm whales are the natural predator of giant squid.

So pieces of the creature have been found in their stomachs and they even sometimes get scars of huge sucker marks with squid that put up a But how does that explain the legends of kraken attacking humans?

Well, octopuses have attacked swimmers and divers.

We have the footage.

But there's another element at work, sharks.

We need to take these predators into account when talking about the kraken.

Though shark attacks are rare, they do happen.

Often all witnesses would see is a flailing body, blood, and maybe even the victim dragged under the surface of the water, but no evidence of what was causing the attack.

This established idea that large creatures in the ocean posed a threat to humans.

Combine that with sightings of the alien body of a giant squid or a large tentacle and the kraken legend begins to take form.

To quote Hugo, "These animals are indeed phantoms as much as monsters.

They are proved and yet improbable."

The kraken is unnerving, because it resembles a real animal.

Sure, we don't have conclusive evidence of one over 50 feet long, but we've only measured about 500 giant squid throughout recorded history.

We can hardly call that a representative sample of an entire species.

All we really have are glimpses of a creature we don't completely understand.

The relatively few species we do know about in the deep ocean are frightening, because they seem otherworldly.

We don't need to look to space for aliens.

They exist right here in the uncharted territories of Earth.

Even more bizarre creatures may exist in the dark depths of our oceans, inspiring authors to craft even stranger, more terrifying sea monsters.

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