Rebecca has inherited her grandmother's Gothic mansion and brings both her best friend an her boyfriend for a weekend. While exploring the crypts they discover an old dusty book, which describes the life of a vampire. As the story unfolds, it becomes apparent that the vampire was Rebecca's great grandfather, Rico.

Based on the true events that occurred in the Appalachian Mountains, Mountain Devil recounts the frightening events of the night Frank Peterson and his friend spent the night in a secluded cabin stalked by something they could not explain. With only a few clues and journal entries we try to piece together the shocking events, and attempt to shed insight into one of the greatest mysteries of our time