Both Henry James's 1880 novel Washington Square and The Heiress, the 1949 film directed by William Wyler, follow young Catherine Sloper (Olivia de Havilland). She is an inhabitant of Washington Square with her father, Dr. Austin Sloper (Ralph Richardson). Unfortunately, Catherine's mother has died; and her father is not a loving parental figure. In fact, Catherine and Dr. Sloper have a mutual disdain for each other. Dr. Sloper succeeds in nearly ruining his daughter's life. He tells her what to do and when to do it.
Catherine does end up finding a little bit of happiness in Morris Townsend (Montgomery Clift), a charming, handsome man. The two of them start a relationship, much to the chagrin of Dr. Sloper. He believes that Morris just wants to marry Catherine for the money. He does not believe that his daughter is beautiful or charismatic enough to score with a man like Townsend without some kind of catch to it. Unfortunately, it is very possible the good doctor is right because Morris disappears when he learns that Dr. Sloper will disinherit Catherine if she marries him.
Both the novel and the movie are very similar. But, at the end there is a very noticeable difference in Catherine's attitude. In Washington Square, Catherine simply and politely decides against going back to Morris when he returns years later, old, fat, and bald. She seems to have gotten past the relationship and merely wants nothing to do with him.
In The Heiress when Morris comes calling (still handsome, not so many years later) Catherine lets him have it. She is angry, and she does not care to let Mr. Townsend know it until her "big moment." She lures him into thinking that she will go off with him later on that night, as they had planned to do before when he had stood her up. Then she has the maid, Maria (Vanessa Brown), bolt the door, and ascends the stairs, triumphant torch held high, while Morris pounds on the door in vain.
I must say that I enjoyed the end of The Heiress a little more than the other. Morris used her and she, in return, made him feel her pain. Catherine's attitude seems a little more fitting in the movie. Her father has conditioned her to be a mean, unloving person. She has indeed learned from the best.