There’s something deeply relatable about a passive, people-pleasing introvert somehow becoming BFFs with an extrovert who dubs themselves “The CEO of Fun.” No matter which side of this friendship you’re on, you can understand the draw these kinds of people have on one another. The former needs someone to drag them out of their shell, and when an extrovert gets paired up with an introvert like that, they often dial the gregariousness up to 11 to balance things out.
The last thing I expected from Amazon’s new shark movie was for it to meditate upon this exact kind of often toxic codependent relationship. Long before a bull shark gets dumped into a freshwater tunnel system in Thailand and starts mauling tourists, The Devil’s Mouth is already simmering with tension between best friends Max (Lana Condor) and Sara (Kathryn Newton). The origin story of their friendship is a complex one, and the relationship already feels strained when they start their once-in-a-lifetime vacation fresh out of college with three other chums: Max’s boyfriend James, along with another couple, Greg and Adrienne. (While Sara is ostensibly a fifth wheel, she and Max’s bond is the strongest connection on display.)
Out today on Prime Video, The Devil’s Mouth is directed by Jeff Wadlow, who’s made a career out of slick, high-concept genre movies (usually horror) that often crumple under the weight of cumbersome mythology. (The Rotten Tomatoes scores across his filmography does not inspire hope.) I have fond memories of watching his feature-length debut Cry Wolf (2005), a teen slasher based on the Mafia/Cry Wolf party game that’s secretly more elaborate and psychologically nasty than its B-movie skin suggests. There are echoes of that complexity lurking underneath it all in The Devil’s Mouth, which boasts a screenplay by Aja Gabel and Myung Joh Wesner that appeared on the 2019 Black List under its original title, Apex.
That original script had some noteworthy differences. For one thing, its female leads were frenemies trapped in a love triangle, allowing old tensions and power struggles to resurface while they fought to survive once the bull shark shows up. Apex was also set in Mexico, which only reinforces the suspicion that The Devil’s Mouth uses Thailand largely as exotic set dressing. Beyond some beautiful establishing shots and the presence of an exceedingly charming local guide named Wat (The White Lotus’ Tayme Thapthimthong), the story could happen inside virtually any similar cave system. Yet these particular caves are beautiful enough to make you want to plan a vacation, even though you know there’s a shark about to show up.
Gabel and Wesner retain sole writing credits on The Devil’s Mouth and refined the character dynamics and motivations of its leads. After the death of her father, Sara spiraled into depression and almost dropped out of college. Max rose to the occasion and became something between a best friend, surrogate sister, and overbearing parent. Sara loves Max for saving her life, but she also seems to resent the permanent claim Max now seems to have over her. At the start of the movie, Sara appears ready to move on. Exploring the cave system that her late father once called life-changing is positioned as some kind of closure for the darkest chapter of Sara’s life. Max supports her friend in this endeavor — as long as she can party along the way and somehow make everything about her.
Condor is terrific at making this contradiction believable. Max is bossy, selfish, and frequently unbearable, but never so monstrous that Sara’s devotion becomes difficult to understand. She feels like somebody you’ve met before in real life. For all Max’s faults, her and Sara’s mutual affection is sincere, even if Max fails to recognize that Sara doesn’t need a CEO of Fun to cheer her up anymore. She just needs a friend. Newton gives a much quieter performance — at least at first — feeling like a meek wallflower and fifth wheel while the two couples pack on the PDA and get drunk on a small yacht.
Sara’s seemingly nervous and anxious attention to detail gives way to a levelheaded kind of efficiency once the group encounters saltwater fish in a freshwater cave — and realizes something followed the storm surge inside. Somebody nervously points out that bull sharks can survive in freshwater, even though they seem to prefer the ocean.
That tidbit of trivia gives The Devil’s Mouth just enough scientific plausibility to deliver what seems like a ridiculous premise. The premise also plays directly to Wadlow’s strengths. There’s no elaborate mythology to explain. There’s just murky water and a labyrinthine system of underwater caves. Most shark movies typically take place in broad daylight where you see the fin a mile away before the predator’s big grin churns out of the water. Here, the shark might disappear for minutes at a time only to surge out of nowhere and begin slamming a victim against the limestone walls.
One of the cleverest things about The Devil’s Mouth is how it makes a series of monotonous caves look legible. There’s a whole scene when the group arrives, ready to take the easy green route, before the CEO of Fun demands they take the advanced red path. As characters move back and forth through the system, the camera overlays the map so we always have a strong sense of where they are. It’s a smart way to avoid what could have easily been a huge fumble.
Max drags Sara onto the dangerous path because she considers herself the adventurous, capable one. Max — and we as the viewer — see Sara as fragile and assume she might crumble under overwhelming pressure. Yet when the shark arrives, Sara is the only person who consistently keeps her head. Hers is a story about resilience, of transforming under pressure and stepping outside the shadow of an overbearing friend. Newton does an exceptional job at showcasing each layer to Sara, whether it’s the depressed introvert or the emerging hero of it all.
The character dynamics give The Devil’s Mouth a lot more bite than you’d expect from a straight-to-streaming shark movie. Wadlow stages the underwater horror with clarity, Newton and Condor sell a friendship that is both sustaining and suffocating, and the finale delivers the satisfyingly nasty payoff every shark thriller demands. Beneath the murky water, The Devil’s Mouth understands that sometimes toxic friendships can be just as scary as a hungry bull shark. In both cases, it’s usually best to get as far away as humanly possible.
The Devil’s Mouth is now available to stream on Prime Video.
