The ocean is full of weird and wonderful creatures, especially the unexplored depths.  Creatures like the Fangtooth and Anglerfish are the stuff nightmares are made of.  So it is little surprise that some of the most iconic horror films have been inspired by creatures from the sea.  These six aquatic horror movies take full advantage of the strange mysteries of the sea….

Open Water (2003)

The film is claimed to be loosely based on the true story of Tom and Eileen Lonergan, who in 1998 went on a scuba diving trip on the Great Barrier Reef, and were accidentally left behind because the dive-boat crew failed to take an accurate headcount.  They soon find themselves struggling for survival in shark-infested waters.

The film was financed by the husband and wife team of writer/director Chris Kentis and producer Laura Lau, both avid scuba divers.  Working on a U.S. $120,000 budget, duo filmed Open Water on weekends and holidays for three years off the coast of Bahamas. They shot more than 120 hours of footage. Daniel Travis and his co-star Blanchard Ryan are both certified scuba divers who worked with real sharks. “We thought we would have to swim with two or three sharks,” said Travis, who plays one half of the stranded couple. “But when we showed up for filming there were about 45 or 50 of them.”  The film ultimately grossed $55.5 million worldwide.

The Host (2006)

The storyline features a monster kidnapping a man’s daughter, and his attempts to rescue her. According to the director, his inspiration came from a local article about a deformed fish with an S-shaped spine caught in Han River. The Host set a new Korean box office record by reaching 10 million tickets in just 21 days. In addition, it was ranked one of the top films of 2007 on Metacritic with a score of 85.

Some of the filming took place in the real sewers near the Han River, rather than on a set.  During filming, the crew had to deal with the effects of changes in weather and ambient temperature. This including the sewage water freezing in cold temperatures, so that it had to be broken up and melted; and during hot and windy periods, the water evaporated and the silt turned to dust, which blew around in the breeze and into the faces of the crew. Eww!  Sounds like a real life horror just shooting this film.

Deep Blue Sea (1999)

A group of researchers try to find a cure for Alzheimer’s disease by genetically modifying shark brains. However, trouble ensues when the now-smarter sharks hunt down their creators.

When he was growing up in Australia, Deep Blue Sea screenwriter Duncan Kennedy saw the remains of a shark attack victim, which had washed up near his home. “There was really not much left of him,” Kennedy told the Los Angeles Times. Kennedy had nightmares about being trapped in a passageway with sharks that could read his mind, and channeled those dreams—and his childhood experience—into the script about sharks whose brains have been modified by a scientist conducting Alzheimer’s research, making them smarter and much more deadly.

War of the Worlds (2005)

In this classic, Ray Ferrier, a dockworker, and his children are all set to spend a weekend together. However, an alien tripod descends on Earth, threatening to wipe out humanity.

The design of the aliens are based on jellyfish, with movements inspired by red-eyed tree frogs, and an amphibian quality particularly on the wet skin. The “Ulla” war cry of the Tripods was made with a didgeridoo and computer effects.

Tremors (1990)

The premise of the film follows natives of a small isolated town as they defend themselves against strange underground creatures called ‘tremors’ which are killing them one by one.

These ‘tremors’ are actually inspired from Devil worms, which have been discovered miles under the Earth—the deepest-living animal ever found.  The worms are also able to survive in waters with extremely low levels of oxygen, lower than one percent of the level of most oceans.  It can withstand extreme heat and pressure, and also chew through your dreamcatcher…eeek!


After a space merchant vessel receives an unknown transmission as a distress call, one of the crew is attacked by a ‘Xenomorph,’ a mysterious chest bursting life form, and they soon realise that its life cycle has merely begun.  With Box Office earnings of up to $203.6 million this could be one of the most successful horror films of all time.

As for the creature that inspired the “Alien?”  Meet a parasite that can create its own mobile nursery for its young, a parasite that is thought to be the inspiration behind the Xenomorph in the film Alien. Meet Phronima, a parasite found throughout the world’s oceans, except polar regions, swimming in open water. Their bodies are semitransparent. Instead of constantly feeding on a live host, females attack Salps, using their mouths and claws to eat the animal and hollow out its gelatinous shell. Phronima females then enter the barrel and lay their eggs inside, and then propels the barrel through the water as the larvae develop, providing them with fresh food and water.

Do you have any examples of movie monsters inspired by marine animals that we’ve missed? If so, take to social media and share your creative examples with us!

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