The film begins with a group of sorority sisters—Cassidy, Jessica, Ellie, Claire, and Megan—attending a party at a sorority house. During the party, Megan discovers that her boyfriend, Garrett, has been cheating on her. In retaliation, Megan decides to prank Garrett by faking her own death with the help of her friends.
The prank involves pretending to accidentally kill Megan with a drug overdose and then making it look like her body is disposed of in a nearby abandoned mine shaft. However, the prank takes a deadly turn when Garrett, unaware that Megan is faking her death, panics and actually kills her by accident.
In a panic, the sorority sisters decide to cover up Megan’s death to avoid getting in trouble. They agree to keep the incident a secret and dispose of Megan’s body in the mine shaft. However, someone witnesses their actions from a distance.
Eight months later, the sorority sisters are preparing for graduation when they begin receiving threatening messages from an anonymous sender. The messages indicate that someone knows what they did and intends to seek revenge. The girls initially dismiss the threats as a prank, but they soon realize that they are being targeted by a mysterious killer.
As the killer begins picking off the sorority sisters one by one, the remaining girls must race against time to uncover the identity of the murderer and put an end to the killing spree. Along the way, they uncover dark secrets and betrayals within their own ranks.
In a climactic showdown, the killer is revealed to be Megan’s vengeful sister, Maggie, who blames the sorority sisters for Megan’s death. Maggie seeks revenge by systematically targeting each of the girls involved in the cover-up.
The final confrontation takes place in the sorority house, where Cassidy manages to outsmart Maggie and ultimately kills her in self-defense. With the killer defeated, Cassidy and the remaining survivors are left to deal with the aftermath of the ordeal, knowing that their lives will never be the same again.