In the small town of Ottawa, Illinois, where a rumor can spread like the plague and nobody's business is their own, six friends decide to change their weekly routine of watching movies in the basement and talking shit, to go out for a night on the town. On most nights this wouldn't be that taxing. But tonight isn't most nights. With rumors of the police commissioner's alleged disappearance circulating, and the mayor enacting a strict curfew, it doesn't take long for things to spiral out of control and the whole town to go mad. Is it just hysteria? Is it a curse? Is it Abraham Lincoln's fault? Nobody knows. But for the gang, only one thing is certain. They should have NEVER left the basement.

Billie, a twenty something burnout, is tasked with house-sitting for her aunt and uncle, but after inviting some friends over, becomes convinced her teenage cousin Grace has stolen a notebook containing her latest screenplay. While hunting for the book in "Grace's Room", the gang uncovers a bloody trove of occult paraphernalia. Unbeknownst to Billie and her friends, said cult has been watching them from the nearby woods, and now must kill them for discovering too much. A gruesome assault on the house ensues as the gang struggles to survive the night.