Kleptomania as a substitute for nymphomania
Yes, Dorothy's kleptomania is pleaded for as a disease by her sister, which is certainly consonant with 1950s social thinking, but it struck me that the word is also a metaphor for her nymphomania -- especially in the beach house scenes, first with Ben Grace, and later when she makes the switch to Sully. She is sexually suggestive, aggressive, and opportunistic.
This presents an intriguing moral contrast with her sister, who is also motivated by a kind of greed -- as Ben Grace notes in an early scene -- but it is one of the socially approved kinds -- a relationship, though they are not married -- with her boss who is powerful and rich, but an idealist, while she is "practical."
So I don't think the good girl-bad girl stereotypes are so stereotypical here, but complex.
Benedictus.
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