You may find this analysis of American Beauty by Brittany Deschlar interesting:
There are many connecting themes in American Beauty. Through plot, characterisation, and cinematography these themes are conveyed well. Overall, this film is highly successful in layered themes and counter themes. The main themes that the film draws attention to throughout the movie are that of materialism, appearance versus reality, denial and repression, control versus chaos, loneliness versus feeling connected, change and searching, and beauty (subjective and objective). Each character is an agent in one or more of the themes as explained below.
One of the most apparent themes in this film is that of the empty promises of materialism. The American Dream is what the Burnhams seem to have: good jobs, a house in the suburbs, children, two cars, and a nice home. The Art Culture Film website describes them as “trapped by the ideology of the American Dream”. Carolyn Burnham is obsessed with materialism and other’s opinions of them. She loves her house and possessions and to her these things equal success. Mendes shows in the scene in which Lester is trying to kiss her and show Carolyn they can still experience passion. They are on the couch and she almost submits to the moment when out of the corner of her eye she notices that Lester is about to spill beer on her couch and warns him. Lester, frustrated, yells, “It’s just a couch!” to which she replies that it is not just a couch, but one that cost $4,000 and is upholstered in Italian silk. In a scene in which she fights with her daughter, Carolyn yells at Jane for not appreciating the life she has (meaning the possessions she owns.) Material accumulation is what she views as a means to being happy, and does not understand that her daughter would benefit more from a close relationship with her mother.
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