You need to watch the weirdest sci-fi thriller on Amazon Prime ASAP

“If you gaze long into an abyss, the abyss also gazes into you.” Frederich Nietzsche's provocative philosophies often focused on man’s will to power, which the famous philosopher describes as humanity’s main driving force but never fully defines. The question of what drives us to action is a common one in movies, so it’s no surprise that this 2017 sci-fi thriller opens with what’s arguably Nietzsche's most famous quote before mining his philosophy for mind-bending scares.

Director Xavier Gens explores concepts of colonialism, feminism, revenge, and the endless nature of war. Not too shabby for a movie with only three main speaking roles.

Cold Skin resides somewhere between King Kong: Skull Island, The Lighthouse, and The Shape of Water. Set at the dawn of World War I, the movie focuses on David Oakes’ “Friend,” a character without a formal name despite his role as a scientific official meant to chart wind patterns on a remote island. The film offers a prologue between Friend and John Benfield’s Captain Axel, with the audience guided by Friend’s narration. The captain is older than Friend and has been tasked with his safety, but a bond beyond formalities exists between them.

There are reasons for Axel to be concerned for Friend’s safety. The man who Friend was supposed to replace is nowhere to be found with the island's only inhabitant being an unruly and unkempt lighthouse keeper named Gruner (Ray Stevenson, one of the Warriors Three of Thor) who seems to care more about tobacco provisions than any wind measurements.

The unspoken kinship between Friend and Captain Axel is fascinating. The two push and pull at each other while barely saying a thing. Axel’s caution eventually gives way to Friend’s sense of impending doom and a brotherhood is cut short, leaving Friend to deal with Gruner on his own.

At first, this suits each man just fine. The two have nothing in common, with Gruner stomping around his lighthouse shirtless and Friend cataloging wind speed. During his time off, Friend reads his predecessor's journals, which include troubling notes like “DARWIN WAS WRONG.” But a bizarre nighttime attack on Friend’s home by mysterious creatures forces his hand: the two must join forces to defend themselves.

These creatures quickly become the focus of the movie. Amphibian, blue, bipedal, and bitey, Gruner has been fighting them off for some time from his lighthouse. They come from the ocean and only attack at night. But even more intriguing is that Gruner has kept one of them around him, seemingly as a pet. The creatures are also revealed to have healing powers, able to lick Friend’s wounds to health. Gruner explains that like a dog, this creature, which he calls a toad, will not leave him no matter how poorly he treats her.

This is not the sort of thing that a conscientious pet owner says. As you can imagine, Gruner is treating this toad rather poorly. He beats her and also has sex with her, although Friend is becoming more and more fond of her. Friend is in no real position to do anything, however, because other toads are attempting to storm the lighthouse and seemingly kill them.

After Friend faints during their first nightly battle, Gruner gives him one more chance. He forces Friend to kill toad after toad on his own until his face is covered in blood. Personalities aside, an alliance is formed.

It’s clear that Gruner’s pet has intelligence, and Friend decides to humanize her with a name, Aneris. Played by actress Aura Garrido, Aneris is a master-class in practical effects. She does not communicate with words, but there’s a sense of her being trapped in an abusive relationship.

In a 2018 interview, director Xavier Gens (who previously directed the 2007 Hitman movie) mentioned that Garrido trained for two months just “learning how to move, how to express her emotions with her body.” She also had to show up to work every day naked, which led to the movie being filmed in the Canary Islands.

While Aneris doesn’t speak English, it is clear she is communicating with her brethren somehow, possibly encouraging them to attack. Despite Gruner and Friend seemingly wiping out hordes night after night, their numbers continue to rise. With ammunition running low, Friend makes the decision to explore a nearby ship’s wreckage in hopes of ending the attacks once and for all.

Unlike many movies with few characters, Cold Skin doesn’t feel small. Perhaps this is because there are armies of toads attacking regularly, but it’s also because Gens’ camera is so actively, constantly moving around the movie’s two protagonists as if he is trying to figure them out himself.

There are no clear answers to the many questions presented in Cold Skin, and in some ways, this is very appreciated. But in both Gruner’s description of the humans as invaders and the film’s calling attention toward World War I, Cold Skin suggests that war never really ends, it just takes different forms. Where structures may fail, individuals can find themselves free.

As David Oakes says in a behind-the-scenes clip, Cold Skin is “genuinely odd.” If you’re looking for a monster movie that takes the road less traveled by, check out Cold Skin.

Cold Skin is streaming now on Amazon Prime and IMDb TV in the U.S.