X2 writers Mike Dougherty and Dan Harris apply their talents to the teen slasher genre, delivering a horrific update to the well-known legend of Bloody Mary. It's 1969 and Mary Banner is a bookish, unpopular girl who has unexpectedly been invited to the dance by a star athlete. His intentions are less than admirable, however, and after trying to escape from him Mary suffers a long and painful death. Years later in 2005, Sam (Kate Mara, TV's JACK & BOBBIE) and her girlfriends are having a slumber party on prom night, and while discussing urban legends and local lore, they invoke Mary's name and bring her back from the dead. This sets off a string of local murders, each executed according to the dictates of a different urban legend. Sam and her brother David (Robert Vito, SPY KIDS 3: GAME OVER) take it upon themselves to investigate, researching the original crime in an attempt to thwart the revenge the wronged spirit is determined to see through.