This film charts the slow descent of a French girl, Carol, played by Catherine Deneuve, into madness and horror. The acting in this film is superb, and especially by Deneuve, who brings to her part a delicate balance of vulnerability and strangeness. Right from the start, there is a sense that this beautiful, introverted, seemingly harmless girl, is not 'quite all there.' Give her a slight push, and she will tumble into total madness. As a performance, it is reminiscent of Anthony Perkins in Psycho.
The camera is on Carol all the time, and we see events unfold through her paranoid and schizophrenic mind. We feel her isolation. The mundane is amplified -the ticking of a clock, the sounds of the street outside, the toiling of the bell from the next door nunnery-and made to seem menacing. She is dependant on her sister to such an extent that when her sister goes to Italy on holiday, leaving her alone, she loses her lifeline on which to grasp for human contact. Her isolation is so intense that other people become a threat. Those who are a menace to her, such as her landlord, are treated in the same manner as those who wish her well, such as her boy friend. She can no longer tell the difference. The madness in her mind is made manifest on the screen: Huge cracks appear in the wall symbolising the cracks appearing in her mind. Hands come out of the wall and touch her. Her nightmares torment her with physical contact of men, the one thing that horrifies her, and which are made utterly believable by the vagueness of the camerawork and the silence on the soundtrack-how very much like a real nightmare. The structure of the film is marvellous, as is the cinematography. There is not a shot or a frame wasted as every scene, every shot, builds up to show Carol's loosening grasp of reality.
One of the greatest films of the 20th Century. On every level, this film not only works, but works brilliantly. Roman Polanski is a genius, and this film is his cinematic masterpiece.