Linda Rodgers is gang-raped while tending to her horses at a boarding stable. Disturbed by the brutal attack, Linda's grip on reality becomes increasingly weakened, propelling her into a psychotic break in which she enacts bloody revenge.
This lackluster and tacky "I Spit on Your Grave" knockoff seems to be striving to be a psychological character study, but the script, direction, and performances never really get it to that point. There is little in the way of narrative; the film inexplicably begins virtually in medias res as Linda is raped at a horse stable, and the remainder of the film feels like a series of stitched-together scenes that never propel the plot forward.
Uninventive, dry camera-work leaves the film feeling visually bland, which is another major detraction; the least one could hope for is an at least mildly aesthetically pleasing film, but sadly that is not the case. The performances are far from great, although I don't think they are quite as bad as some may have suggested—by eighties low-budget horror standards, they are more or less average. Sallee Young plays the tortured protagonist and is on and off the mark, playing her psychosis scenes in an exaggerated childlike pose; in spite of its imperfections, her performance is weirdly disturbing. Porn star Harry Reems plays her unfaithful husband and is somewhat memorable, while a series of unknown actors play her thug rapists. The conclusion is considerably disturbing, though it also plods along at the same pace as the rest of the picture.
Overall, "Demented" is a cheap and tacky effort, and an obvious attempt to capitalize on the rape-and-revenge popularity after "I Spit on Your Grave." It's a technical hodgepodge, marred by lazy cinematography and a weak, single-note script. That said, Young's performance is notably twisted, and the film does attain a dreary and disconcerting atmosphere. It's not a gem, but it's also not quite as terrible as some may lead you to believe. 4/10.
