At Camp Clear Vista, Sam hides in a cabin and calls Chuck, a horror-movie buff, insisting that a masked killer is roaming the campgrounds. On the line, Sam is pressed for details and begins recounting his first day at the camp with fellow counselors and several friends, including his ex-girlfriend Imani.
While still on the phone, Sam blacks out and awakens to the cabin going up in flames. He escapes, catching a glimpse of the masked killer before finding a new hiding spot. With Chuck’s steady questions, Sam pieces together more events and memories as fear tightens its grip around the camp. After discovering several dead bodies, the group realizes they are effectively trapped there, cut off from help.
As they patrol the woods for the killer, Sam stumbles upon Freddie and Nancy, who for some reason cannot hear him. He watches the killer slaughter them, then suffers another blackout, leaving him smeared with blood and holding both the killer’s weapon and a mysterious wooden mask. The two of them conclude that Sam might be the killer himself. The blackouts grow longer and more perilous, moments when the supposed “killer” personality seems to take over.
Sam makes several clumsy attempts to destroy the mask, but the relic stubbornly resists. Chuck wonders if the mask has imprinted on him, and the fear of being hunted by the other counselors drives Sam back into hiding. Chuck urges Sam to remember how everything began, and the story unfolds in a fever dream of memories.
The origin of the mask stretches back to the early days of European colonization, when Cajun settlers brought dark magic to the land. The magic spirals out of control, releasing a malevolent entity that possessed people and drove them to massacre each other until a powerful sorcerer sealed the entity inside an oak tree. Centuries later, The Wood Carver fashions a mask from a tree that still harbors the spirit. Under the mask’s influence, the carver murders many before he himself is killed by a young woman and buried with the mask.
The fearsome history lures the campers into a desperate search for the grave. One of Sam’s friends, Drew, tricks him into revealing the woodcarver’s resting place. Drew uncovers the mask and, ignoring warnings not to wear it, places it on Sam as a joke. Possessed, Sam seizes the woodcarver’s weapon and kills Drew, deepening the chilling mystery surrounding his fate.
As the body count climbs, Sam recalls more murders, including the brutal act of throwing Imani into a spike pit. His feelings for her momentarily break the spell long enough to remove the mask, but the danger remains ever-present. Chuck advises that the surviving two women, including Jamie, could be the Final Girl—the lone figure who can end the curse.
A supernatural compulsion pulls Sam back into the mask, and he kills Brad in a grisly blaze of violence. Imani crawls from the spike pit, having faked her death, and reunites with Jamie. The two manage to knock the mask off Sam and lock him in a shed, while Chuck explains the Final Girl dynamic to the two remaining young women.
Despite their careful efforts, the mask finds its way back to the two, and Sam breaks out once more, sending Imani and Jamie fleeing. Believing she will survive as the Final Girl, Imani attempts to kill Jamie, but Jamie kills her instead, shifting the burden of fate onto the remaining survivor. Chuck tells Jamie that she must kill Sam at the woodcarver’s grave—the site of power where the curse began.
With great effort, Sam tears off the final remnants of the mask and heads toward the graves with Jamie. He argues that they can end the nightmare by burying the mask together, and Jamie initially agrees—only to be drawn to the mask herself when she touches it. Wearing the mask, Jamie drives the woodcarver’s blade into Sam, killing him, and then strides away with the relic.
Two years later, Chuck receives a call from a panicked Sam, who has become undead, leaving the future of the camp—and everyone who survived—the subject of unanswered questions and a haunting, unresolved waiting.
