Artist Sal Devito (J.J. Barry) and his girlfriend Jackie (Carole Shelyne) are city slickers who have moved to the rural town of Stowe, Vermont. A year ago, shortly after they arrived, Sal accidentally hit a young girl (Karen Lewis) with his car, killing her. Ever since then, the girl's grandfather, elderly loner Ned McDermott (William Robertson), has hated Sal. Lately, Sal has been suffering from seizure-like fits in which he sees a hooded figure watching him, and begins to suspect that he has been cursed. He goes to see Adrianna Putnam (Kim Hunter), a local psychic, to help him cast off the curse.
Dark August contains examples of:
- Accidental Murder: Sal was found innocent of manslaughter - the girl ran right in front of his car, too quickly for him to brake - but McDermott doesn't care.
- Alone with the Psycho: Jackie sneaks into McDermott's house. While she's snooping around his basement, he walks up behind her and grabs her by the neck. She manages to fight him off and escapes with the wax ball he's been using to do his magic.
- Black Cloak: The figure manifests as a tall man in a cloak with his face completely covered.
- Evil-Detecting Dog: Sal's dog Mona whimpers and growls whenever the hooded figure appears. At the end of the movie, Sal and Mona are tracking the figure in the forest when Mona suddenly attacks Sal, forcing him to shoot her.
- Fire Purifies: Adrianna tells Sal to do a ritual that involves burning his studio down. Sal does what she asks, but before he can finish, the fire department arrives and puts out the fire, preventing the ritual from working.
- Freeze-Frame Ending: The credits appear over a freeze-frame of Sal kneeling over Mona's bloody corpse.
- Hoist by His Own Petard: McDermott is killed by the hooded figure when he interrupts a ritual to dispel it.
- No Name Given: McDermott's granddaughter is never named. She's credited as "The Child."
- Pistol-Whipping: McDermott bursts into the ritual to dispel the demon, shoots Arianna, and hits Theo in the head with the butt of the rifle.
- Scenery Porn: There are many shots of the beautiful forests and mountains surrounding Stowe.
- Special Thanks: "Thanks to the town of Stowe Vermont and Harriet Lewis."