When Matthew Sullivan's elderly uncle is told he needs to clean his property or lose it, Matt begrudgingly begins to help the hoarder start organizing his home. As he cleans, he discovers references to a grandmother the family never discusses. His curiosity piqued, Matt asks his uncle what happened to her and receives stubborn silence. Confused and curious, Matt begins to dig into his family's history. As he scrapes the surface, he receives a phone call from an estranged family member who is running for president of the United States and is told to stop immediately. The call only galvanizes his need to discover what really happened to his grandmother, Katherine Sullivan. Matt's investigation leads him to a small town in West Virginia, deep in the mighty Allegheny Mountains, where he begins to uncover the terrifying truth of what really happened on that fateful day in 1948.