As the vibrant art festival comes to an end, four hopeful actors gather to explore the unconventional filmmaking style of the enigmatic director Jett, portrayed by Jett Garner. The aspiring talent includes Catherine, played by Elise Muller, Michelle, characterized by Greta Gerwig, and Chad, depicted by Steve Zissis. With a budget that's almost a joke, Jett reveals his shocking technique of keeping the cast completely uninformed until the project was finalized. While some marvel at his audacity, others can only shake their heads in disbelief. Their thoughtful discourse takes an unexpected turn when the excitement of an after-party beckons. However, Matt, played by Ross Partridge, wrestles with indecision and hesitates to approach Jett for a VIP entry, fearing he may come off as desperate.
Refusing to let themselves be overshadowed by the city’s glamour, the group opts for a creative retreat at Chad's rustic cabin nestled in the woods. The initial thrill of this getaway quickly fizzles out when Michelle, after indulging in too many drinks, retreats to her room. What follows is an awkward encounter with Chad, whose advances she rebuffs, likening him to a brother. In an emotional bid for clarity, she rushes outside only to encounter a mysterious figure cloaked in secrecy - a man wearing a bag over his head.
As days stretch into one another, Michelle believes this bizarre sighting to be merely a figment of her intoxicated imagination. Yet, upon sharing her eerie experience with the group, they rally around the idea of creating a horror film centered on the haunting "Baghead." When night falls, brainstorming fuels creativity, and Michelle initiates veiled exchanges with Matt, hinting at a secret rendezvous in her room. Unbeknownst to her, a shadowy figure – the dreaded Baghead – watches her intently. Initially misjudged as Matt, the enigmatic presence escalates Michelle's anxieties, leaving her to question the true identity of this stalker.
Amid the escalating tension, suspicion lace the air, as Catherine's jealousy towards Michelle's growing bond with Matt reaches a critical point. This emotional turmoil prompts her to storm off, abandoning a cacophony of unresolved feelings. It falls upon Matt to reason with Michelle, ensuring her that their artistic purpose is worth the struggle, despite the increasingly surreal events surrounding them.
As dawn breaks, Chad's frantic search for Catherine proves fruitless, leading him to confront Michelle about her deepening relationship with Matt. However, his anger abruptly dissipates when an alarming scream shatters the stillness of the woods – a sign that ominous happenings are afoot. When the group finds Chad’s torn shirt, they dismiss it as a prank, unaware of the brewing turmoil sparked by Michelle's affections. Tension escalates further when Matt finds himself confronted by hooded figures in the upstairs room, revealing the perilous dynamics between him, Chad, and Catherine, who seek retribution for perceived betrayals in a brutal twist of fate.
As night descends, the atmosphere thickens with dread. The sudden appearance of a figure at the window amplifies their shared panic, and upon investigation, they discover their vehicle is disabled, leaving them trapped in a suspenseful game of cat and mouse with the lurking Baghead. In a desperate bid for survival, Matt and Chad provoke the harrowing figure, only to retreat in terror when they realize he bears a knife. They barricade themselves in the cabin, praying for daylight.
The next day, the group, driven by survival instinct, challenges themselves to hike the treacherous 11 miles to the nearest freeway. Hours of wandering leave them lost and bewildered until they stumble upon an abandoned car. Just as Chad prepares to break the window for help, the dreaded Baghead reemerges, provoking sheer pandemonium. In a horrific turn of events, Matt is brutally murdered before his friends' very eyes. The surviving duo of Catherine and Michelle make a desperate dash to the freeway, flagging down cars that conveniently ignore their plight.
Meanwhile, Chad, edging closer to the road, meets with tragic misfortune when he is struck by a passing vehicle. As he lies unconscious, Catherine and Michelle rush to aid him, only to find themselves at the hospital later, grappling with the impact of Matt's violent fate. Once awake, Chad learns the devastating truth - Matt had orchestrated the entire nightmare, capturing it all on film for his ambitious project. In a shocking twist, Chad, still grappling with his grief, proposes to cut the footage and submit it to a festival, convinced of its possibility for success.
