You could call The Devil’s Mouth a shark thriller of the familiar sort, but it is a solid one. In a streaming landscape cluttered with creature features, this film has enough bite to its claustrophobic atmosphere and poisonous friendships to put it on the map.
Prime Video has put it out there during the height of Shark Week, and the story takes us to Thailand with a coterie of American friends fresh from college for some luxury time off. Then there are the two at the centre of things: Sara (Kathryn Newton), who is the more reserved and obliging of the pair, and her lifelong friend Max (Lana Condor). A self-styled “CEO of fun” with a controlling streak and the privilege to back it up, Max is used to having the world and Sara revolve around her whims. Along with them are Max’s boyfriend James (Nico Hiraga) and the rather expendable Greg (Gavin Casalegno) and Adrienne (Tommi Rose).
Things go awry on an early trip on the yacht when Max’s thoughtlessness results in a jellyfish sting for Sara. Undeterred, the party goes ahead with a guided cave swim in a remote coastal area known as the Devil’s Mouth. Their local guide, Wat (Tayme Thapthimthong), counsels them to take the safer option, but they see fit to disregard him. Storms have upset the natural order of the place and a bull shark has made its way into the waterlogged tunnels. From there you get the usual run of hostilities and sudden violence as the group attempts to make their exit through ever-narrower passages with the predator on their trail.
Jeff Wadlow makes the most of his surroundings in this one. The director, with a Black List script from Aja Gabel and Myung Joh Wesner to work from, capitalises on what the setting has to offer. There is a real sense of claustrophobia in the caves that you do not get from your typical open-water shark affair. Some of the underwater work is quite suffocating in effect, not least a scene where the characters are in a race for air through ever-narrowing quarters.
Then there is the matter of interpersonal friction. Max will not cede control or be held to account, and as the pressure mounts it forces Sara to face up to just how lopsided their friendship has been. Wadlow presents it as a coming-of-age issue as much as a question of survival: at what point do you put an end to someone else calling the shots, even if it leaves you swimming on your own?
Do not expect any genre reinvention here. The characterisations are thin, the trauma backstories seem to be there because they should be, and the CGI shark has neither personality nor much of a visual threat. The gore is held in check for the PG-13 rating, the pacing can lag between the attacks and the denouement is something of an anti-climax. But for mid-tier streaming fare, The Devil’s Mouth does what it says on the tin. You have your young stars and some scenic Thai locales, plus the odd jump scare and a human drama that is a little more interesting than the usual formula.
Newton is the one who stands out, putting some grit and feeling into a part that might otherwise have been all reaction. Condor appears to have fun being at odds with her normally wholesome persona. They provide a certain rooting interest absent in most body-count shark films. In a year we have seen our share of aquatic predators, that is enough of an edge to make this worth your while, as long as you are in no hurry to leave the comfort of the couch.
You will not find much of substance in the average streaming shark thriller; they are content to let cheap jump scares and a mindless body count fill out the running time. The Devil’s Mouth is another matter. For all its genre conventions, it has a way of working because it does not shy away from putting some real toxic interpersonal dynamics at the heart of the terror.