Gone Girl is a contemporary thriller novel by American writer Gillian Flynn.
Gone Girl takes up the story of Nick and Amy Dunne's difficult marriage, which is floundering for several reasons. Nick, a former journalist of some seriousness, loses his job due to downsizing. In a somewhat desperate state of mind, he relocates himself and his wife from New York City to the small Midwestern town of North Carthage, Missouri, where Nick is from. There, he opens a bar, using the last of his wife's trust fund, and runs it along with his twin sister Margo. The bar provides a decent living for the three Dunnes, but the Dunne marriage becomes more and more dysfunctional. Amy loved her life in New York and hates what she considers the soulless "McMansion" which she and Nick are now renting.
On the day of Nick and Amy's fifth wedding anniversary, Amy goes missing. Nick eventually becomes a prime suspect in her disappearance for various reasons. He used her money to start a business, increased her life insurance, and seems unemotional on camera and in the news.
In the first part of the novel, the reader does not know whether Nick is guilty. He does have morbid visions of Amy, but makes himself sound too innocent to commit such crimes. The first half or so of the book is told in first person, alternately, by both Nick and Amy; Nick's perspective is from the present, and Amy's is in the past by way of journal entries. The two stories are very different. Amy's account of their marriage makes her seem happier and easier to live with than Nick depicts. Nick's story, on the other hand, talks about her as extremely anti-social and stubborn. Amy's depiction makes Nick seem a lot more aggressive than he says he is in his story.
In the second half of the novel, the reader sees that Amy and Nick are deceitful narrators and have not given all information. Nick has been having an affair and Amy is actually alive and hiding, trying to frame Nick for her death. The diary she kept earlier in the novel is fake, intended to implicate Nick further to the police.
However, Amy is soon running low on money when she is robbed by fellow guests of a motel. Desperate, she seeks help from an old friend. He agrees to hide her, but Amy soon feels trapped in his house. She murders him and returns to her husband, saying she had been kidnapped. Nick knows that she is a killer, but he stays in his marriage because she is pregnant with his child. The book ends with Amy writing that she is about to give birth to her son, and that she has written a memoir about her so-called abduction and imprisonment.