Nightmare Man (2006)

Plot

Ellen's life spirals into chaos after she mistakenly receives a mysterious mask, triggering terrifying hallucinations and waking nightmares. Misunderstood by her husband and doctors, she is admitted to a psychiatric ward for what they believe is paranoia. However, when their car breaks down en route to the hospital, Ellen's husband leaves to find help, and the sinister Nightmare Man emerges. Fleeing to a nearby country house occupied by two couples, Ellen faces a chilling uncertainty: is the killer real or merely a manifestation of her fractured psyche, and is he lurking outside or hidden within the house?