Dr. Rosemarie Boyer, a brilliant prion disease specialist, returns to her childhood home, Hollow Creek, to find her best friend Sarah in distress and the town plagued by a mysterious fog and strange behavior. As Rosemarie delves deeper into the town's dark history, she uncovers a centuries-old pact made by her ancestor, which has trapped a dark entity within the earth. With the help of Krista, a reclusive woman, Rosemarie must use her compassion and empathy to break the pact and free the entity, restoring peace to the town.