I took this description of the film from Rotten Tomatoes. Read what Mark Deming has to say about the film:
Director Sam Mendes, made his feature film debut with this film about the dark side of an American family, and about the nature and price of beauty in a culture obsessed with outward appearances. Kevin Spacey plays Lester Burnham, a man in his mid-40s going through an intense midlife crisis; he’s grown cynical and is convinced that he has no reason to go on. Lester’s relationship with his wife Carolyn (Annette Bening) is not a warm one; while on the surface Carolyn strives to present the image that she’s in full control of her life, inside she feels empty and desperate. Their teenage daughter Jane (Thora Birch) is constantly depressed, lacking in self-esteem, and convinced that she’s unattractive. Her problems aren’t helped by her best friend Angela (Mena Suvari), an aspiring model who is quite beautiful and believes that that alone makes her a worthwhile person. Jane isn’t the only one who has noticed that Angela is attractive: Lester has fallen into uncontrollable lust for her, and she becomes part of his drastic plan to change his body and change his life. Meanwhile, next door, Colonel Fitts (Chris Cooper) has spent a lifetime in the Marine Corps and can understand and tolerate no other way of life, which makes life difficult for his son Ricky (Wes Bentley), an aspiring filmmaker and part-time drug dealer who is obsessed with beauty, wherever and whatever it may be. American Beauty was also the screen debut for screenwriter Alan Ball.
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