POPCORN

Film student and screenwriter Maggie Butler has recurring dreams of a girl named Sarah, caught in a fire and chased by an assailant. She documents these on an audio tape in the hopes of making them into a film.

Maggie's classmate Toby D'Amato proposes hosting a horror movie marathon to raise funds for the film department, to be held at the abandoned Dreamland theater. He enlists the help of Dr. Mnesyne, who lends them film memorabilia from his shop.

In his inventory, they find a short cult film called Possessor, which resembles Maggie's dreams. Lanyard Gates, the director, killed his family while shooting the final scene, then set the theater on fire. When Maggie asks her mother Suzanne about the film, she dismisses it, urging Maggie to quit the festival. Later, Suzanne receives a call from someone who tells her to meet them at Dreamland and bring a gun. Once there, she has visions and is attacked by a shadowy figure.

The night of the festival, a suspicious man buys a ticket from Maggie and calls her "Sarah" before entering. Maggie tells Toby, but he dismisses it. The first movie is a 3D film, Mosquito. Mr. Davis prepares a giant mosquito prop, but while he's flying it above the audience, a mysterious figure causes it to fly into him, stabbing him with its stinger. In a laboratory, an unknown being then makes a copy of Davis's face.

The second film is The Attack of the Amazing Electrified Man, featuring a "Shock-o-Scope" gimmick consisting of electrical "buzzers" in seats. Bud, a student who uses a wheelchair, prepares the seat shockers as Maggie re-listens to her audio tape and hears a message from "Gates". Backstage, Mark's date Tina attempts to kiss Davis, but his face melts off and he strangles her. The killer then straps Bud into an electric chair prop for the film and electrocutes him to death, shutting off the theater's electricity.

Maggie is confronted by Gates and realizes that she is Sarah Gates, that Lanyard is her father, and that Suzanne is actually her aunt who rescued her from the Possessor fire long ago. She flees and explains this to Toby, believing Gates has returned for her. After Toby and Maggie enter the basement and restore the power, he disappears and she is again confronted by Gates.

When the power returns, Maggie is strapped to a chair in the killer's lair. Toby, revealed to be the killer, explains that he was badly burned as a child while attending the Possessor screening with his mother, who was in Gates' film cult and was killed that night. Blaming Maggie and Suzanne, he plans to exact revenge on them by re-enacting the final scene of Possessor on stage tonight.

The third film is The Stench, in "Odorama". Joanie, realizing she's behind for her Odorama cue, leaves to join Leon. Meanwhile, Toby shows Maggie that he has encased Suzanne in a full body cast, pointing her gun. Leon goes to the restroom and is met by a doppelgänger who locks him in a stall and triggers a lethal poisonous gas, killing him. Dressed as Leon, Toby returns to the booth with plans to stab Joanie but storms out when she mentions her unrequited love for Toby.

Mark arrives at Toby's apartment to find that he is being evicted. The walls are plastered with articles of the Possessor incident, including pictures of his facial reconstruction and Maggie with scissors in her eyes. Horrified, Mark rushes back to the theater.

The final scene of Possessor is simultaneously being screened and re-created on stage: Maggie is locked in a metal dress, and despite her pleas to be saved, the audience believes it is a part of the act. Mark uses the mosquito track to zip line onto the stage, causing the mosquito to swing around unlatched and stab Toby in the chest, killing him. Mark releases Maggie and Suzanne as the crowd erupts in applause.