A recurrent, unidentifiable noise in her apartment. A memo to her boss that's replaced by obscene insults. Amanda - a successful architect in a happy marriage - finds her life going off kilter by degrees. She starts smoking again, and one night for no reason, without even the knowledge that she's doing it, she burns her husband with a cigarette. At night she dreams of a beautiful woman with pointed teeth on the shore of a blood-red sea.

The new voice in Amanda's head, the one that tells her to steal things and talk to strange men in bars, is strange and frightening, and Amanda struggles to wrest back control of her life. Is she possessed by a demon, or is she simply insane?