This novel is about life after World War I. Times and values were changing fast. The morals were "loosening up" and the fashions were getting riskier for women. Those with money were spending their money recklessly and acting recklessly. In fact, Fitzgerald predicted the crash of 1929 in this novel. He saw the American Dream falling, and that's exactly what happened just a few years after the novel was published.
The story is told through the eyes of Nick, the narrator. He meets Jay Gatsby who lives in a huge mansion next door to him. Jay has come to the "West Egg" to win back the heart of Daisy Buchanon, who just happens to be Nick's cousin. However, she is already married. Jay's goal is to win her back and take her away from her current husband Tom. Tom and Daisy live in the East Egg, and they represent a different type of (careless and reckless) rich. Through Nick's eyes we see Jay win back Daisy's heart, but then fall because of the type of person she truly is. Upset in the end, Nick goes back home to the Midwest disgusted with what people have become.