After losing her mother in an accident, a teenager and her father welcome a distant cousin into their home. Hoping to claim the family as her own, the psychopath hatches a devious plan to recreate the prom she never experienced.

Lucy Jacobs is a small-town girl who has started her freshman year at a big-city university. When Lucy returns home for Thanksgiving break, she suspects she is about to get turkey dropped: dumped by her high school sweetheart.