Miss Chris MacNeill, actress, finds out her daughter Regan has the signs of an illness. Doctors don't have an explanation and are wordless. Despite this, the girl goes on featuring weird powers like levitation, superhuman strenght and lots more. Science gives up at last, while a priest-exorcist is called. Initially skeptic, Father Karras asks the help of expert exorcist Father Merrin: they quickly realize this is not a case of simple mental disorder.

This movie is a true horror. The possession scenes are absolutely realistic and troubling to watch: Regan's spider, walk for instance, is one scene. to no miss The voice of evil makes you tremble. We are brought slowly to the violence of the Devil for good. An anti-Evil movie that explores the darkest sides of humanity, between faith and evil. Visual effects are used to express the wildest evilness humanity can imagine: from the purity of a child to the rough madness that ruins her body and life. Linda Blair's performance is brilliant and convincing.