Katie (Jenny McCarthy) and Becky (Pamela Anderson) are talking about a tape, which Katie thinks is a sex tape, but Becky refers to a cursed tape (The Ring). After several odd occurrences, they die one-by-one. In a farm outside Washington, D.C., a widowed farmer and former reverend, Tom Logan (Charlie Sheen) and his clumsy younger brother George (Simon Rex) discover a crop circle, saying "Attack Here!" (Signs).
Meanwhile, Cindy Campbell (Anna Faris), now an anchorwoman, announces the crop circles on the news. She picks up her paranormally endowed nephew Cody (Drew Mikuska) from school, where her best friend Brenda Meeks (Regina Hall) is his teacher. George Logan arrives to pick up his niece Sue, Tom's daughter, who is in the same class. Cindy falls in love with George, who invites her and Brenda to a rap-battle with his rapper friends Mahalik (Anthony Anderson) and CJ (Kevin Hart) (8 Mile). George competes and proves to be actually quite talented, but due to unintentional racist blunders he's thrown out.
Later, Brenda asks Cindy to keep her company, since she watched the cursed videotape. After playing several pranks on Cindy, she gets the rest of the popcorn in the lounge, when the TV turns on. Brenda fails to turn it off. Tabitha (Marny Eng) climbs out of the well and the TV, Brenda gets into a fight with Tabitha. Tabitha ends up killing Brenda, since Cindy is ignoring the ruckus. George receives a phone call about the death, and Tom meets with Sayaman, who apologizes for the accident involving himself and Tom's wife Annie (Denise Richards).
During Brenda's wake, George and Mahalik, through a misunderstanding, wreak havoc on Brenda's corpse in attempt to revive her, only to blow up her body and end up getting kicked out of the house. Later, Cindy decides to watch the tape, finding it odd. She then gets a phone call, saying she'll die in a week. She calls George, CJ and Mahalik for help. CJ offers that his Aunt Shaneequa might be able to help. Aunt Shaneequa (Queen Latifah), the Matrix Oracle, and her husband Orpheus (Eddie Griffin) agree to watch the tape. Shaneequa discovers the hidden image of a lighthouse, and gets into a fight with Tabitha's mother. Shaneequa tells Cindy to find the lighthouse to break the curse. When Cindy returns home, she finds Cody watched the tape.
Back at work, Cindy searches through pictures of lighthouses before finding the one from the tape. Desperate to save Cody, Cindy tries to warn everyone by entering a message into the news anchor's teleprompter, but she is interrupted by her boss and a janitor who insults the manager on the teleprompter (which the anchorman blindly recites). The Logans hear the message and take it seriously since they encountered an alien disguised as Michael Jackson, and President Baxter Harris (Leslie Nielsen), who personally visits the farm to investigate the crop circles. Cindy ventures to the lighthouse, where she encounters The Architect (George Carlin). The loquacious (and lecherous) old man explains Tabitha was his evil adopted daughter, whom his wife drowned in the farm's well, but not before she imprinted her evil onto the tape. Unfortunately, he mistook the evil tape for a copy of Pootie Tang and returned it to Blockbuster instead, unleashing the curse.
Returning home, Cindy discovers her station has been broadcasting the evil tape for hours, and there have been various sightings of aliens around the world. Worse, Cody is missing. Cindy manages to track him back to the Logan farm, where he has taken refuge with George. Tom orders everybody into the basement for safety, as he, George and Mahalik go outside to fight off the extraterrestrials. The aliens (voiced by Tom Kenny) arrive but reveal they are friendly and have come to stop Tabitha, since they accidentally watched the tape on a broadcast they had intercepted, thinking it was Pootie Tang.
In the basement, Cindy realizes the farm's cellar is what is seen on the tape and she finds the well where Tabitha was drowned under the cellar floor. Suddenly, Tabitha appears behind her. A short fight ensues, during which Tabitha takes Cody hostage. Cindy and George appeal to her, offering her a place in their family. Tabitha appears to accept the offer, but then changes back to her monstrous form and advances to Cindy and the others, only to be accidentally knocked back into the well by President Harris. The aliens leave in peace, and Cindy and George get married. Leaving for their honeymoon, they realize they forget to take Cody with them. At first, Cody is about to get hit by Cindy's car in an intersection, but she put the brakes this time to prevent it from happening, much to Cody's relief. Unfortunately, another car passes by on the intersection and hits Cody.