- Alternate Character Interpretation: Due to not wanting to hinder Montgomery Clift's status as a romantic leading man, the movie made some changes to Morris's personality, intentionally allowing for this trope. The answer to the question of his true intentions with Catherine changes from he definitely only wanted her money to he probably only wanted her money.
- Hollywood Homely: Olivia de Havilland as the plain Catherine.
- Misaimed Fandom: After the release of The Heiress, Olivia de Havilland actually received hate mail from fangirls of Montgomery Clift who completely missed the point of the story.
- Woobie: Many of Catherine's lines towards the end of The Heiress really exemplify how cruelly she had been treated in her life:Aunt Penniman: Can you be so cruel?
Catherine: Yes, I can be very cruel. I have been taught by masters.