Plot
In 1994, Heather, a bookstore employee at the Shadyside Mall, is fatally stabbed by her friend, Ryan Torres. He murders her and six other mall employees before he is shot dead by Sheriff Nick Goode. The media reports the massacre as the norm for Shadyside, which they dub the murder capital of the United States. Meanwhile, the neighboring town of Sunnyvale is its polar opposite, as it is considered one of the richest and safest towns in the country. Many of the Shadyside teenagers believe that this is the result of the witch, Sarah Fier, who placed a curse on the town before being executed for witchcraft in 1666.
Deena Johnson does not believe in the Fier witch and has recently broken up with her closeted girlfriend, Sam, who had moved to Sunnyvale. Josh, her brother, spends his time researching the town's history, and her friends Simon and Kate sell drugs in hopes of eventually leaving the town. Deena and Sam meet again at a vigil in Sunnyvale for the victims of the mall killings, where a brawl between the students of Shadyside and Sunnyvale breaks out. While returning home, Sam's boyfriend, Peter, begins tailgating the bus carrying the Shadyside students, leading Deena to almost throw a large cooler at the car in retaliation. A sudden nosebleed causes her to lose her grip on the cooler, and Peter's car to crash. Sam survives and sees a vision of Sarah Fier before being taken to the hospital.
The following night, Deena and her friends begin being stalked by someone they initially believe is Peter and his friends. However, when Deena and her friends visit Sam, Peter is killed by Skull Mask, who proceeds to murder two others in the hospital and is revealed to be an undead Ryan. Sam and Deena seek help but fail to convince the police, while Simon is attacked by Ruby Lane, one of Shadyside's past killers from 1965. The group realizes that the car accident disturbed Sarah Fier's grave and that Sam bled on her bones, resurrecting several Shadyside killers. Josh deduces that Fier's curse is the reason for Shadyside's history of killings, which began following her execution. They attempt to offer her a proper reburial, but are attacked by the Camp Nightwing Killer. Realizing that the killers only want Sam and are attracted to her blood, they set a trap at school in an attempt to destroy the killers by burning them, but the killers manage to reanimate.
Sam reluctantly agrees to be sacrificed with the group despite Deena's protests. They save her when it is discovered that C. Berman, a survivor of the Camp Nightwing massacre in 1978, claimed to have seen the witch. They attempt to call her but receive no answer. Sam finds out that C. Berman also died, but was resuscitated. The group organizes a plan to kill and revive Sam using drugs from a supermarket pharmacy. There, Kate, Simon, and Josh attempt to fend off the Shadyside killers, but Kate ends up murdered by Skull Mask with a bread slicer and Simon gets an axe to the head by the Camp Nightwing Killer. Deena finally drowns Sam, causing the killers to disappear, and revives her using a combination of EpiPens and CPR.
Afterward, the police decide to place the blame on Simon and Kate, as they were known for selling drugs. Sam and Deena reconcile and publicly come out as a couple. Later that night, while Sam is at her house, Deena receives a call from C. Berman, who tells her that there is no escaping the witch. Sam, now possessed, attacks Deena but is subdued and tied up, with Deena promising to find a way to free her.
