I found most of the plot somewhat unrealistic in that Irena (the cat woman as it were) falls in love with an American man (Oliver) who she marries. Due to her worring about having sex with her husband and killing him in a cat like rage she tells him that she can't be his wife in the fullest sense of the word and he is quite excepting of this for some months. I'm not sure that even in the 1940's that a married man would except his wife not consumating the marrage, it all seems a little hard to believe. But Oliver ends up sending her to a psychiatrist believing her to be suffering from a paranoid superstition. In one part of the film Oliver, Irena and Alice (a friend of Oliver and rival to Irena) are in a museum and Oliver sends his wife Irena away so he can be with Alice, giving Irena justification for her to be upset and further her paranoia. You tend to feel sorry for Irena more than find her a menasing foe that will claw you to death. You just don't get the impression she is a bad person, as the New York Times state "Miss Simone's (Irena's) cuddly little tabby would barely frighten a mouse under a chair".
This film though does have some scenes that have been mimicked by many others due to their tence nature, for example when a bus comes screeching into shot when Alice is being followed by Irena.