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. Written by unknown

Let Her Out follows Helen, a bike courier who suffers a traumatic accident. As she recovers, she begins to experience strange episodic-black outs, hallucinations, and night terrors-that lead her to discover that she has a tumor, a benign growth that is the remnants of a "vanishing twin" absorbed in utero. Over time, the tumor manifests itself as the dark and demented version of a stranger. As Helen's emotional and psychological state begins to deteriorate further and further, she begins to act out in psychotic episodes that are influenced by her evil twin - making her a danger to herself and her best friend, Molly.