In The Heiress, which is William Wyler's 1949 movie version of Henry James's 1880 novel Washington Square, Catherine Sloper goes through a type of "Cinderella" transformation.
Catherine, played by Olivia de Havilland, Catherine begins the movie as a quiet and naïve girl who is looked down on by her father (Ralph Richardson). She never really speaks out much and prefers not to anger anyone. At the start of the movie, Catherine goes into her father's study, where he criticizes her. Throughout the entire movie her father always tells her that she is not really worthy of people's affection, especially a man's. But still Catherine says nothing to him, keeping her feelings hidden so she is sure not to upset her father.
Catherine also is timid when it comes to matters with Morris (Montgomery Clift). She always lets him do what he wants. She does not fight him off when he has her cornered in the study and kisses her; she also lets him make all the decisions for their elopement. So not only does she consistently want to please her father, but also she feels the same for Morris.
By the end of the movie, Catherine has made it to a point of transformation. Her breaking point has been the night that Morris jilted her. At this point one sees a change in Catherine's character. She becomes more outspoken, and her entire demeanor changes. She no longer seems to care what people are thinking about her. She begins to gain the same self-confidence that Cinderella has at the ball.
The most obvious change that she goes through is at the end of the movie when Morris, who now wants to be her Prince Charming, comes back to her. She tells Morris that she agrees to marry him again, but one can see the wheels turning in her head. She decides to give Morris a dose of his own medicine. Whenever he comes back later that night, she leaves him knocking on the door, calling out her name. Catherine, untouched, walks up the stair, head held high, just listening to Morris scream for her and pound on the door. By the look on her face, one can see that she has finally gotten the revenge on her Prince Charmless she had hoped for.