* AdaptationDisplacement: More people know the movie than the play or the book.
* AlternativeCharacterInterpretation: The film pushes the question whether Rhoda's sociopathy is influenced by her serial killer grandmother's genes or from being spoiled rotten all her life, though more likely it's a combination of ''both''; her genes may have not affected her so much had she not been spoiled and led to believe she should have anything that she wants. Christine, after all, has those same genetics and turned out fine, relatively.
** Has Rhoda really been spoiled, at least by her parents? Christine tried to make Rhoda accept the loss of the medal graciously and seems concerned that Monica keeps showering Rhoda with gifts.
* NightmareFuel: Everything. About. Rhoda. EVERYTHING.
* [[HesJustHiding She's Just Hiding]]: We never do see Rhoda's body after the lightning strikes the pier, though that could be because of censorship at the time or the fact that that bolt of lightning incinerated her body to ash. There's also a splash in the water just off the pier about two seconds after the lightning bolt.
* TheWoobie: Christine, and especially Mrs. Daigle, who only has vague suspicions about what really happened to her son that no one takes seriously.