Once Upon a Time in a Horror Movie (2026): Cast, Story and

Prepared by Movies Dock Editorial

A birthday celebration takes a terrifying turn when friends enter an immersive 1980s slasher experience and discover that the boundary between performance and reality is disappearing. Once Upon a Time in a Horror Movie blends horror, thriller and drama elements around a desperate race to survive until the final reel.

Once Upon a Time in a Horror Movie takes a familiar horror setup and places it inside an interactive movie experience. A group of friends expects an unusual birthday celebration, but the promised 1980s slasher fantasy soon becomes much more dangerous than planned.

Written and directed by Ashley Cahill, the 2026 film combines horror, thriller and drama elements in a compact 1-hour-23-minute runtime. Its central question is simple: what happens when a game designed to imitate a horror movie begins to feel real?

Once Upon a Time in a Horror Movie movie details

Story without spoilers

The film follows a group of friends who sign up for an immersive horror-movie experience as part of an unforgettable birthday celebration. The attraction is built around the idea of placing participants inside their own 1980s slasher film, giving the group a chance to act out the conventions of a classic horror story.

As the night continues, however, the distinction between make-believe and reality starts to collapse. What begins as entertainment turns into a fight for survival, with the group facing a straightforward but urgent objective: stay alive long enough to reach the final reel.

What to expect

The premise points to a horror thriller shaped by slasher-movie conventions, an enclosed experiential setting and escalating uncertainty about what is part of the performance. The drama element suggests that the story is not limited to its survival mechanics, though the supplied information does not specify its particular character or emotional focus.

With a runtime of 83 minutes, the film offers a relatively concise setup for its transition from birthday celebration to life-threatening ordeal. The 1980s slasher framework is central to the concept, while the immersive format provides the story’s main source of tension.

Cast and creative team

Ashley Cahill serves as both director and writer. The cast includes Mabel Thomas as Erika, Neeley Dayan as Katie, Shane Graham as Gordon, Alison Gold as Charlotte, Alex J. Joseph as Dylan and James DeBello as Rusty.

• Mabel Thomas as Erika
• Neeley Dayan as Katie
• Shane Graham as Gordon
• Alison Gold as Charlotte
• Alex J. Joseph as Dylan
• James DeBello as Rusty

Release and production context

Once Upon a Time in a Horror Movie is a 2026 English-language film with a listed release date of October 9, 2026. It is classified as Horror, Thriller and Drama, and has a runtime of 1 hour and 23 minutes. The supplied information does not identify a country or production company.

Movies Dock view

Once Upon a Time in a Horror Movie is built around the uneasy transition from staged terror to genuine danger. Its immersive 1980s slasher premise, focused cast and compact runtime give the film a clear genre identity without requiring a larger mythology to explain its basic stakes.

Film data:
TMDB