This article contains full spoilers for The Devil’s Mouth.
The Question Before the Water Closed Over Them
There are films I begin by asking whether they are any good.
I began The Devil’s Mouth with a simpler, more urgent question: do they all die?
Closely followed by: is there a final girl?
This is what happens when a film combines a flooded cave system, limited oxygen, unseen passages, rising water and something large moving underneath the surface. I have what I continue to describe, without professional confirmation, as undiagnosed thalassophobia. I do not like deep water. I do not like dark water. I especially do not like water where the bottom has apparently resigned and left no forwarding address.
Then there are sharks.
I hate fuckin’ sharks.
Not in the ecological sense. I understand they have a role, that they are not malicious sea gangsters and that humans have done considerably more damage to sharks than sharks have done to humans. All very reasonable. None of it matters when a dorsal fin appears. Between being eaten by a shark and drowning while trying not to be eaten by a shark, I do not want either option. I would like the third choice, involving dry land, a chair and perhaps a beverage.
And yet Kathryn Newton is in the film, so apparently I am watching.
Released globally on Prime Video on 29 July 2026, The Devil’s Mouth follows five friends whose Thai holiday descends into a flooded-cave survival ordeal after a violent storm allows marine life, including one particularly committed bull shark, into a supposedly freshwater cave system. The film runs for approximately 105 minutes and was directed by Jeff Wadlow from a screenplay by Aja Gabel and Myung Joh Wesner.
What follows is essentially a shark film squeezed through the architecture of a cave thriller, with friendship drama pushed into the gaps between the rocks. It is familiar material. We have seen attractive young people ignore warnings before. We have seen sharks behave as if they hold personal grudges. We have seen the cautious woman discover that caution, competence and a well-packed first-aid kit are more useful than swagger.
The distinction is in the pressure.
There is no open horizon here. No boat to climb onto. No beach in the distance. The water is trapped inside the rock, and so are the people.
From Apex to Thailand in Ten Days
The Devil’s Mouth is not based on a novel, a true story or a pre-existing franchise. It began as an original screenplay titled Apex, which appeared on the 2019 Black List of well-regarded unproduced scripts. Wadlow became attached to direct in 2023, with Amazon MGM Studios, Lionsgate and Thunder Road eventually bringing the project to the screen.
The original script was set in Mexico, and the production had been preparing to shoot in the Dominican Republic. Then, only around ten days before the company was due to travel, facilities and experienced water-production crews became available in Thailand. Wadlow suggested moving the entire story there, which required a rapid rewrite and a practical recalibration of the film’s geography.
That last-minute shift could easily have made Thailand feel like interchangeable scenery: cliffs, boats, bright water, ominous caves, job done. The film does occasionally lean towards travel-brochure shorthand in its opening stretch, but the setting eventually earns more weight than that. The limestone formations, enclosed waterways and contrast between tropical light and subterranean darkness give the film a clear visual progression.
The holiday begins in open air. Bodies lie in the sun. Music plays. Everyone is attractive and temporarily convinced that youth, money and a hired guide will protect them from geology.
Then the ceiling comes down.
Production took place over eight weeks in Krabi province, Chiang Mai and Bangkok. Two weeks were spent on location, followed by six weeks filming on soundstages. Rather than constructing thirteen entirely separate cave environments, the production team built two main flooded sets and altered their rock formations, colours and identifying details to create the illusion of a much larger underground system. One set measured roughly 120 by 70 feet and held about five feet of water; another smaller set was built in a tank approximately fifteen feet deep.
This matters because the cave does not feel like one damp room photographed from twelve angles. Individual chambers have different textures and threats. Some are wide enough to offer false relief. Others force the characters into narrow channels where turning around becomes difficult. The rock is never neutral. It scrapes, traps, divides and redirects.
The cast also spent a considerable amount of time physically in the water. Lana Condor described days lasting twelve or thirteen hours in the tanks, while Gavin Casalegno recalled stretches reaching fourteen hours. Kathryn Newton performed much of her own climbing and swimming work, sustaining the sort of cuts, bruises and shredded knees that arrive when artificial cave walls remain considerably more solid than an actor’s skin.
Whatever else does or does not work, the discomfort has not been added entirely in post-production.
Five Friends, One Guide and Several Bad Decisions
The group consists of Sara, played by Kathryn Newton; Max, played by Lana Condor; Max’s boyfriend James, played by Nico Hiraga; Adrienne, played by Tommi Rose; Adrienne’s boyfriend Greg, played by Gavin Casalegno; and their guide Wat, played by Tayme Thapthimthong.
The film introduces them as a recognisable holiday unit rather than fully separate lives.
Sara is the sensible one. Max is the organiser and self-appointed leader. James is the accommodating boyfriend who has learned that resistance usually adds twenty minutes to the conversation. Adrienne is the party girl. Greg is her loud, physically confident jock boyfriend. Wat is the professional who knows the landscape and whose advice will naturally be treated as optional.
This is the sort of group where warning signs are not so much missed as put to a vote.
The most important relationship is between Sara and Max. They have been close friends for years, but they have reached the point where shared history has begun disguising an unequal dynamic. Max assumes she will lead. Sara assumes she will adjust. Even their future has apparently been organised this way. Sara has a job waiting in New York, but Max has decided that Los Angeles makes more sense for both of them.
It is presented as friendship, but the film keeps revealing the management structure underneath.
Before the cave expedition, Max already shows how her appetite for experience outweighs her concern for Sara. A jellyfish encounter leaves Sara frightened and isolated, but Max treats it as another inconvenience to be pushed past. Later, after a storm has made conditions uncertain, Wat recommends caution. Max presses forward. Sara has reservations. Max presses forward. An easier route is available. Max wants the more difficult one.
Max does not merely make decisions. She treats other people’s uncertainty as a personal insult.
May I just say: Max is annoyingly annoying.
Not enjoyably abrasive. Not secretly wise beneath the bossiness. Annoyingly annoying. She is pushy, controlling and so convinced that momentum equals leadership that she repeatedly turns caution into a character flaw. Condor gives her enough force to prevent the role becoming entirely cartoonish, but the writing stacks the evidence heavily. We are not gradually discovering that Max’s confidence is dangerous. The film is practically holding up a waterproof sign.
Sara, the Girl Scout and the Waterproof Map
Sara accepts a life jacket when the others do not. She carries practical equipment. She knows first aid. She keeps hold of the map. When Adrienne cuts her leg, Sara is the person prepared to deal with it. When the cave system becomes unstable, Sara studies the available routes instead of assuming confidence will somehow produce an exit.
She is, as the group jokes, the girl scout.
In a lesser version of this story, that would simply be shorthand for nervousness. Sara would be the cautious friend who needs to learn to loosen up, take risks and stop allowing fear to limit her life. The Devil’s Mouth is smarter than that, although not always subtle about it. Sara’s fear is not the problem. The problem is that she has learned to distrust her own judgement whenever Max is present.
Her journey is therefore not about becoming fearless.
It is about becoming authoritative.
Sara has a personal reason for entering the caves. Her late father once explored the system, and completing the route offers a connection to him that is stronger than Max’s desire for another impressive holiday story. That memory gives the cave emotional significance, but the film does not turn it into mystical destiny. Her father does not guide her through visions or conveniently leave behind a shark-killing manual. The connection is quieter. Sara wants to understand something he experienced, perhaps to occupy the same physical space for a moment.
What she finds instead is a test of everything she has been trained to subordinate.
Newton is well suited to this kind of role because she can make watchfulness active. Sara is not blankly frightened. She is constantly assessing. Her attention moves between the water, the rock, the injured people and Max. The performance lets us see her recognising patterns before she is confident enough to act on them.
That hesitation is essential. A final girl who arrives fully assembled is merely a protagonist. Sara has to build herself from the habits everyone else dismisses.
The life jacket matters.
The first-aid kit matters.
The map matters.
Listening matters.
It turns out the boring person who packs properly is often the one you want nearby when the holiday begins eating people.
Max and the Difference Between Leadership and Control
Max initially appears to possess the qualities a survival film usually rewards. She is decisive, physically capable and unwilling to panic. She keeps people moving. She refuses to accept helplessness.
The trouble is that she cannot distinguish movement from progress.
Her relationship with Sara has conditioned her to expect agreement, and the cave removes the social cushioning that normally makes this arrangement tolerable. Every decision becomes immediate. Every mistake has a physical cost. Max cannot change course without admitting that Sara may have understood the situation better.
So she doubles down.
This is where the film’s friendship story becomes more interesting than the supporting romance material. Max is not simply selfish. She appears genuinely to believe that she is protecting the group. Her control has become so familiar to her that it feels like care. Sara’s resistance therefore registers as betrayal.
The cave does not create this problem. It removes the ability to ignore it.
There is a good psychological horror film hidden inside that dynamic: the slow recognition that a friendship has survived partly because one person has always surrendered. The Devil’s Mouth reaches for that film but must also service the shark, the injuries, the flooded passages and the expected body count. The result is more direct than psychologically intricate.
Max’s behaviour becomes increasingly infuriating because we are meant to see what Sara has spent years negotiating. She is the friend who frames every demand as confidence in your potential. The friend who decides what both of you want. The friend who interprets boundaries as ingratitude.
She is also the sort of person who should never be given operational control during a shark emergency.
James, Adrienne, Greg and Wat
James is Max’s boyfriend, although “boyfriend” sometimes sounds too equal a term for the arrangement. He is pleasant, docile and thoroughly henpecked. Nico Hiraga gives him an easygoing warmth, but James spends much of the film responding to Max’s energy rather than generating much of his own.
He does at least contribute the crucial identification of the predator. Once the group begins piecing together the impossible evidence — dead sea creatures, saltwater contamination and something moving through the flooded tunnels — James recognises that they are dealing with a bull shark, a species capable of tolerating both salt and fresh water.
That element is not complete nonsense. Bull sharks possess an unusual ability to regulate their bodies across a broad range of salinity and have been documented far inland in rivers and other freshwater environments. The film exaggerates the animal’s determination, but the basic premise of a bull shark surviving in diluted or freshwater conditions has a biological foundation.
Adrienne and Greg occupy the louder, less sensible edge of the group. Adrienne arrives as the party girl, while Greg is the idiot jock boyfriend whose confidence seems based primarily on having shoulders. Their relationship is physical, performative and not especially burdened by foresight.
Tommi Rose gives Adrienne more vulnerability once the situation deteriorates. Her leg injury becomes both a practical problem and the film’s most obvious dinner bell. Blood in water is such a fundamental shark-film image that it barely requires explanation. Once Adrienne is bleeding, every quiet patch of water begins to feel occupied.
Greg, meanwhile, is the character most likely to believe that being stronger than the other people means he is stronger than the environment. Cave films exist partly to correct this misunderstanding.
Wat should be the group’s most important resource. He knows the system, understands the storm’s implications and has the local judgement everyone else lacks. Unfortunately for him, he is guiding people whose holiday expectations have already overruled professional advice. Tayme Thapthimthong gives Wat a calm authority without turning him into a mystical local stereotype, although the screenplay ultimately treats him more as a route into the cave than as a fully developed character.
That is a recurring weakness. Outside Sara and Max, the group members are sketched efficiently rather than deeply. They have enough personality to be distinguishable, but several remain closer to survival-film functions than people whose loss changes the emotional temperature.
The Holiday Before the Horror
The opening material on the boat is bright, social and deliberately loose. It gives the actors time to establish the group’s hierarchy while the film quietly places its warning signs.
Max directs the energy. Greg performs. Adrienne joins him. James goes along. Sara watches.
There is also a slightly synthetic quality to the happiness. This is a curated holiday, the kind designed to become a sequence of photographs and anecdotes later. The cave is not merely something they want to see. It is an experience they want to own.
That gives the film a modest contemporary relevance. The group’s choices resemble the logic of experience culture: remote locations, physical challenges and private access, all collected as evidence of having lived correctly. Risk becomes part of the attraction because safe experiences do not photograph as well.
Sara’s reluctance threatens that narrative. Max does not simply want Sara present. She wants Sara to confirm the story Max is telling about them: adventurous friends, inseparable, moving to Los Angeles, facing the world together.
A person with a different job, a different city and a different tolerance for danger complicates the brand.
The storm breaks that curated surface. Sea creatures are washed into spaces where they should not be. Water levels change. Routes become unstable. The cave stops being an attraction and returns to being an environment.
It does not care that they booked.
The Cave Is the Better Monster
The shark will sell the film, but the cave does more consistent work.
Sharks create sharp, immediate fear. A cave creates duration.
The characters cannot stand properly. They cannot see far enough ahead. They cannot know whether a narrow passage will open into safety or close around them. Their lights illuminate only fragments, creating small temporary frames in an otherwise unreadable space. Even before the shark arrives, the cave has already removed control.
James Kniest’s cinematography has the difficult job of keeping the action comprehensible without making the caves look conveniently illuminated. The best passages use headlamps, reflected water and narrow beams to turn the frame into a collection of incomplete information. We see the characters’ faces, then the rock behind them, then perhaps a disturbance in the black surface.
The production design avoids making every chamber uniformly grey. The altered colours and formations help distinguish one section from another, which becomes increasingly important as the group separates and attempts to navigate. The fact that two principal sets were redressed to represent thirteen separate caves is invisible often enough to count as success.
The enclosed setting also solves a basic problem that troubles many shark films: why do the characters not simply leave the water?
Here, leaving the water often means climbing into a worse space. A ledge may be temporary. A chamber may flood. The exit may be beyond another submerged tunnel. The characters are not swimming for recreation once the crisis begins. Water has become the corridor.
This is where my own thalassophobia becomes technically inaccurate but emotionally flexible. Traditional thalassophobia concerns deep, vast bodies of water. The cave pools are not always vast. Some are almost claustrophobically small.
That does not improve matters.
A confined patch of black water containing a shark is not reassuring because the shark has less room. It means I also have less room.
And Then There Is the Shark
The shark in The Devil’s Mouth is extremely motivated.
Possibly too motivated.
Once it becomes aware of the group, it appears to abandon every normal shark responsibility in favour of pursuing these particular tourists through a structurally complicated cave system. It patrols, attacks, rams obstructions and turns up with the timing of a disgruntled building supervisor.
Wadlow has cited Jaws and The Shallows among the film’s reference points, while describing the intended combination as a shark movie fused with claustrophobic cave horror. He also wanted the cave itself to remain as dangerous as the animal.
The design works best when the shark is partially seen. A body passing under murky water. A fin caught briefly by light. The bulk of something moving where the tunnel should be empty. As always, the animal becomes slightly less frightening once the visual effects must show it clearly and repeatedly.
This particular shark also has the aggression setting turned well beyond territorial. The film offers some justification: the animal has been displaced by a violent storm, trapped in an alien environment and surrounded by injured humans. Even so, there are moments when it appears less like a confused predator and more like the cave’s appointed executioner.
That is not necessarily a fatal problem. I did not sit down for a measured documentary about bull-shark behaviour. Shark films require the shark to turn up. The problem comes when its movements feel too precisely coordinated with the screenplay. Suspense becomes scheduling.
Still, the basic combination remains unpleasantly effective.
Drowning is already one of cinema’s most primal fears. Being unable to breathe turns time into a visible threat. Add a shark and every possible escape becomes a negotiation between two forms of death.
Stay under and drown.
Surface and be eaten.
Choose wisely.
Water, Sound and a Score That Keeps Pressing
Bear McCreary composed the score, adding The Devil’s Mouth to a body of work that has frequently moved between large-scale fantasy, horror and muscular genre storytelling.
The music does not try to give the shark an instantly recognisable two-note signature. That territory is taken, and attempting to reclaim it would be unwise. Instead, the score works as accumulating pressure: low pulses, percussive movement and swells that make the cave feel as if it is breathing around the characters.
The sound design is often more effective than the music. Water behaves differently underground. Splashes echo. Voices lose direction. Small movements sound close even when their source is difficult to place. The shark can therefore be suggested through displacement rather than shown.
Silence also becomes suspicious.
A cave should be quiet, but a shark film teaches us that quiet water is merely water concealing information.
The contrast with the early boat sequence is useful. Above ground, music, conversation and bright colour produce an easy social rhythm. Underground, the soundtrack narrows to breath, water, scraping rock and panic. The film strips away the group’s social performance until only their actual habits remain.
Sara observes.
Max commands.
James accommodates.
Greg pushes.
Adrienne reacts.
Wat assesses.
The shark simplifies everyone.
A Final Girl Is Built, Not Announced
The initial question does receive an answer.
Kathryn Newton is the final girl.
The film steadily removes the group around Sara, but the ending is less interesting as a tally of who has been eaten than as the point where Sara finally stops allowing Max to define reality for her. The central struggle has always involved two threats: the shark in the water and Max’s certainty that she knows what Sara should do.
By the final confrontation, Sara’s supposed weaknesses have become her survival system. She paid attention. She kept equipment. She learned the route. She understood that fear contained useful information.
The shark is eventually defeated, but the victory does not transform Sara into an action hero from another film. Newton maintains the sense that Sara is improvising while frightened. Her competence is practical rather than glamorous.
That makes her a satisfying final girl.
The term has sometimes been reduced to a visual category: the last young woman running, bleeding and screaming. The more interesting final girls survive because the film has been quietly teaching them. They collect information. They notice what others dismiss. Their terror does not prevent thought.
Sara’s development also reframes the friendship. Survival requires her to release not only her physical dependence on the group but her emotional dependence on Max’s approval. The cave reduces their relationship to its underlying shape, and that shape is not as mutual as Sara wanted to believe.
Max does not get to carry her authority out of the cave intact.
There is something slightly brutal about that. Sara has to lose almost everything before she can claim ownership of her own judgement. The film could have given their relationship more nuance and therefore made its collapse more painful. Max is rendered so consistently pushy that the emotional separation sometimes feels overdue rather than tragic.
Even so, Newton sells the change.
She enters the cave as someone waiting for permission.
She leaves it as the person who made the final decision.
What Works
The setting is the film’s clearest advantage. Flooded caves create a natural mechanism for suspense without requiring elaborate mythology. Space, oxygen and light are always limited. The geography controls the characters more effectively than any villain could.
Newton gives the film a credible centre. She makes Sara’s progression visible without abruptly changing her personality. The woman who survives is recognisably the woman who entered; she has simply stopped apologising for the qualities that keep her alive.
The physical production also helps. Even with digital extensions and an effects-created shark, the actors are frequently wet, cold-looking, scraped and physically constrained. Bodies interact with the rock and water in ways that give the danger texture.
The film remains focused. It is a shark in a cave. There is no secret corporation, prehistoric civilisation, supernatural curse or post-credit suggestion that the shark has laid eggs beneath Bangkok. Sometimes restraint is simply refusing to franchise the fish.
The toxic-friendship material gives the story more shape than a straightforward sequence of attacks. Sara is not only trying to escape the cave. She is trying to escape an old version of herself.
What Sinks
Most of the supporting characters are thin. Adrienne, Greg and James receive identifiable traits, but not enough inner life to make the losses land as heavily as they might. They are likeable or irritating in the required proportions, then the survival machinery begins processing them.
Wat is especially underused. A local guide who understands the cave could have introduced richer questions about expertise, tourism and the casual arrogance of visitors. Instead, the screenplay needs the holidaymakers to remain exposed, which places limits on how useful he is allowed to be.
Max is effective but overemphasised. Lana Condor commits to the role, but the script seldom allows Max to be right long enough for her authority to feel genuinely seductive. If Sara has spent years following this woman, I wanted to understand more clearly why. A few warmer scenes, or one moment when Max’s decisiveness genuinely saves the group, would have complicated the eventual rupture.
The shark’s persistence can also feel mechanical. There is a line between an aggressive animal and a creature that has apparently read the shooting schedule. The Devil’s Mouth crosses it several times.
The PG-13 approach keeps the violence comparatively restrained. Wadlow has said that rating was the intended target rather than the result of severe cutting. That makes commercial sense for a Prime Video thriller with a young cast, although it also leaves some attacks caught between suggestion and impact. A cave shark film does not need buckets of gore, but physical consequence is part of the genre’s weight.
Finally, the film is recognisable almost from the beginning. Sensible Sara will be underestimated. Max’s confidence will become dangerous. The jock will discover that muscle is not strategy. Blood will attract the shark. The guide’s warning will prove correct.
The journey is more effective than the surprise.
The Shark Film After Jaws
Every shark movie still swims in the water disturbed by Jaws.
Some acknowledge it directly. Others attempt to escape through scale, location or absurdity. Bigger sharks. More sharks. Sharks in storms, snow, tornados, laboratories, underwater stations and holiday resorts where local officials continue to display a remarkable resistance to closing anything.
The Devil’s Mouth chooses location as its variation. The animal is familiar; the architecture is not.
Its nearest modern relatives include The Shallows and the 47 Meters Down films, particularly 47 Meters Down: Uncaged, which also trapped young women inside a submerged cave environment. Wadlow’s own references include The Shallows, while coverage of 2026’s unusually busy crop of shark films has placed The Devil’s Mouth within a continuing cycle of survival stories using sharks to externalise trauma, conflict and the struggle for personal agency.
There is a faint nostalgia in all of this for me, although nostalgia may be the wrong word. Shark films occupy their own shelf in the imaginary video shop: Jaws, Deep Blue Sea, Open Water, cheap creature features with teeth filling most of the poster. You already know the promise. Water, isolation and the gradual discovery that evolution has produced something perfectly adapted to ruining your afternoon.
Streaming has become the new shelf. The poster appears, the title explains the threat, and the film asks for less than two hours of nervous commitment.
What has changed is the emotional framing. The shark is no longer always the entire story. In films such as The Shallows and The Devil’s Mouth, it becomes a violent mechanism through which a young woman processes grief, claims agency or escapes a damaging relationship.
This can become formulaic, but it makes sense. Sharks are indifferent. They do not negotiate, flatter, manipulate or care about social hierarchy. Faced with one, the emotional lies people maintain on land become difficult to sustain.
Max cannot boss the shark.
Sara cannot ask it for permission.
Dry Land Looks Better Afterwards
The Devil’s Mouth does not reinvent the shark film. It relocates it, tightens the walls and gives Kathryn Newton enough room to turn a familiar survivor into a convincing final girl.
It is tense more often than it is surprising. Its cave design is stronger than its supporting character work. Its central friendship is interesting, although written with a marker pen where a finer line might have produced more pain. Its shark is frightening, biologically plausible in its tolerance for fresh water, and psychologically less plausible in its dedication to hunting this exact group across multiple chambers.
I was all in because the premise aimed directly at things I would prefer never to experience. I stayed because Sara’s practical anxiety gradually became the only sensible response in the film.
The ending does not cure her fear. It proves she was right to pay attention to it.
Kathryn Newton gets out.
The water closes behind her.
I remain very comfortable on land.
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