Set in the small town of Devil’s Gate, North Dakota, the film examines the disappearance of a local woman (Regan) and her young son. Schull plays an FBI agent who helps the local sheriff (Frakes) search for answers. Partnering with a deputy (Ashmore), they track down the missing woman’s husband (Ventimiglia) and find that nothing is as it seems.
A notorious cult kidnaps a young girl, and sacrifice themselves by the light of the locust moon. The next morning the girl awakes, caked in dried blood and surrounded by corpses…but safe – or so she thinks. Years later, the locust moon is about to rise again and the girl is captured once more by a surviving member of the cult. She is taken to a remote cabin where she learns that a demon has been growing inside of her all these years, and before the dawn it will rise.