31 It makes the depths churn like a boiling cauldron and stirs up the sea like a pot of ointment.

32 It leaves a glistening wake behind it; one would think the deep had white hair.

33 Nothing on earth is its equal— a creature without fear.

This passage from Job 41 opens Leviathan in thick, Gothic font and hangs ominously on the screen for a few moments as a warning against what you are about to experience. This is the only clue as to what, if anything, the film is ‘about.’ After this, the audience is thrown head first into life on a fishing trawler, but this is like nothing you have seen it before – this is a film more concerned with disorienting and terrifying the viewer than it is about telling us any of the details about life aboard a ship.

The opening shots are chaotic – we hear what is going on before we see it. Limited lighting on the deck obscures the view, so for a long time all the audience is aware of is a loud, rusty clanking sound as – presumably – a winch is pulling something in. Eventually, glimpses of the boat start to appear: a wide iron beam here; a dripping, dark chain there. The cameras, attached to the jackets of the men working on the boat, turn out to sea. The depths ‘churn like a boiling cauldron’, and the ‘glistening wake’ is pursued by hungry gulls. Just as the sea was a character for the writer of Job, so is it the main player in this documentary which plays out like a horror film. It’s a disorienting, nauseating opening to the film and this tone doesn’t really relent for the following 90 minutes.

Over the course of the film the camera gets up close and personal with dead fish, straddles the side of the boat as it topples over wave crests and dips in and out of the foaming water. The ship becomes a death liner, where hundreds of sea creatures are beheaded and gutted. Gore drips down the sides of the crates where fishermen slice open the night’s catch. Blood and entrails spurt out of the sides of the boat, leaving a trail of deep red amongst the white wake. One shot lingers on the bulbous eyes of a beheaded fish. Needless to say, this is a sensory overload, a film that is to be experienced, rather than merely watched. Whether it has a purpose, or whether it needs to be ninety minutes long, remains open to debate, but it’s an undeniably gut-churning, provocative piece of filmmaking.

Amongst all this horror, the filmmakers somehow achieve a kind of macabre beauty to the film, capturing visually arresting moments unlike anything you’ve seen before. The unique conditions on board the trawler mean that Leviathan looks like no other film, where occasionally only certain features are lit up, such as the white horses on top of a wave’s crest, or a flock of seagulls against an inky black sky or the majority of the screen is left dark, creating surreal images through the powerful lighting contrast. None of it quite seems real, like the moment where dozens of starfish float past the camera.

For a film with more fish than people, when the directors decide to focus on the human characters, the result is immensely powerful viewing. Most notably there is a scene where a static camera records a man watching television. We don’t see what it is that he is watching, but you can hear the voiceover and it becomes clear that it is a programme about fishing. The fisherman drifts off to sleep as the show’s narrator talks about a dramatic catch for the crew. In a film full of surreal images, this may be the strangest of them all.

Leviathan is showing at Edinburgh International Film Festival on 27 & 29 June