The Devil’s Mouth is built around a five-friend ensemble led by Kathryn Newton, Lana Condor, Gavin Casalegno, Nico Hiraga and Tommi Rose, with Tayme Thapthimthong also in the principal lineup. The survival thriller sends the group into a flooded cave system in Thailand, where limited oxygen and an underwater predator put every relationship under pressure. The film begins streaming on Prime Video on July 29, 2026; our OTT release guide has the platform and trailer details. It is also part of our July 27 to August 2 OTT roundup.
Cast at a glance
| Actor | Character | Status |
|---|---|---|
| Kathryn Newton | Sara | Principal cast |
| Gavin Casalegno | Greg | Principal cast |
| Lana Condor | Not announced | Principal cast |
| Tommi Rose | Adrienne | Principal cast |
| Nico Hiraga | James | Principal cast |
| Tayme Thapthimthong | Wat | Principal cast |
| Harrison Luna | Ryan, the handsome diver | Supporting cast |
Which character names are confirmed?
Current credits identify Kathryn Newton as Sara, Gavin Casalegno as Greg, Tommi Rose as Adrienne, Nico Hiraga as James and Tayme Thapthimthong as Wat. Lana Condor is part of the principal cast, but her character name has not been listed publicly.
Harrison Luna is additionally credited as Ryan, described in the listing as “the handsome diver.” The movie’s official synopsis does not assign personalities, friendships or outcomes to individual names, so any more detailed role descriptions would be premature before the July 29 premiere.
Kathryn Newton as Sara
Kathryn Newton plays Sara, one of the named characters in the group. Newton has moved between television drama, studio comedy and horror, with major credits including Big Little Lies, The Society and the body-swap slasher Freaky.
That genre experience makes her a natural fit for a film that needs to shift quickly from holiday energy to panic. The available story material does not reveal whether Sara becomes the group’s leader or how her arc ends.
Lana Condor in an unannounced role
Lana Condor is confirmed in the principal ensemble, although her character name remains unannounced. She is best known for playing Lara Jean Covey across the To All the Boys films, and her screen credits also include X-Men: Apocalypse, Alita: Battle Angel and Deadly Class.
The role brings Condor into a more confined survival setup. Any circulating character-name match for her remains unconfirmed.
Gavin Casalegno as Greg
Gavin Casalegno plays Greg. He is most widely recognised as Jeremiah Fisher in The Summer I Turned Pretty, while earlier television appearances include Walker and The Vampire Diaries.
The Devil’s Mouth places him in an ensemble where friendly holiday chemistry has to survive fear, separation and dwindling air. The credits confirm Greg’s name but do not yet disclose his individual backstory.
Tommi Rose as Adrienne
Tommi Rose appears as Adrienne. Her television work includes appearances in Outer Banks, Will Trent and Sweet Magnolias.
Adrienne is shown as part of the cave ordeal, but the pre-release material keeps the character’s choices, relationships and fate under wraps.
Nico Hiraga as James
Nico Hiraga plays James. He is known for the films Booksmart and Moxie, and has also appeared in the series The Power and the romantic comedy Sweethearts.
James is one of the currently named characters, but the official synopsis does not separate his story from the larger group. His function in the crisis should become clearer once the movie begins streaming.
Tayme Thapthimthong as Wat
Tayme Thapthimthong plays Wat. The English-Thai actor is best known as Gaitok in the third season of The White Lotus; his film credits also include Mechanic: Resurrection and Skin Trade.
The casting adds a performer familiar with Thailand-set international productions, but the movie’s pre-release synopsis does not define Wat’s precise relationship to the five friends. No further role details are public.
How the ensemble fits the survival setup
The marketing introduces the central group in bright, open surroundings before moving them into narrow waterways and near-total darkness. That contrast gives the cast two modes to play: the ease of a final holiday together and the mistrust that grows once the escape route disappears.
The premise depends on group pressure more than a lone hero. Limited oxygen means one person’s panic can affect everyone, while the underwater predator makes separation dangerous. Each performance therefore has to keep the group dynamics clear even in darkness and confusion.
Who directed The Devil’s Mouth?
Jeff Wadlow directs The Devil’s Mouth. Basil Iwanyk and Erica Lee are among the credited producers, with Amazon MGM Studios backing the Prime Video release. The film’s central acting challenge is clear: keep the friendships readable even when the characters are wet, exhausted and moving through darkness.
The Devil’s Mouth cast FAQ
Who is in the principal cast?
The principal cast includes Kathryn Newton, Lana Condor, Gavin Casalegno, Nico Hiraga, Tommi Rose and Tayme Thapthimthong.
Who does Kathryn Newton play?
Kathryn Newton plays Sara in The Devil’s Mouth.
What is Lana Condor’s character name?
Lana Condor is confirmed in the principal cast, but her character name has not been publicly announced.
When and where can I watch the movie?
The Devil’s Mouth premieres globally on Prime Video on July 29, 2026.