A main theme of the novel is dishonesty and the superficial nature of appearance, particularly within marriage and romantic relationships. The characters lie to each other and to the reader about affairs and disappearances. Amy fabricates a fake diary to implicate her husband for her disappearance and murder. Flynn says that, in writing the book, she wanted to examine how people within a marriage lie to each other: "Marriage is sort of like a long con, because you put on display your very best self during courtship, yet at the same time the person you marry is supposed to love you warts and all. But your spouse never sees those warts really until you get deeper into the marriage and let yourself unwind a bit."
Reviewers noted the novel's portrayal of the effects of media representation and the blood thirst of the news industry. Nick seems guilty due to media coverage before a trial occurs. Salon.com notes that "Flynn, a former staff writer for Entertainment Weekly, is especially good on the infiltration of the media into every aspect of the missing-person investigation, from Nick's cop-show-based awareness that the husband is always the primary suspect to a raving tabloid-TV Fury, who is out to avenge all wronged women and obviously patterned on Nancy Grace."[2] Entertainment writer Jeff Giles notes that the novel plays on reader expectations that the husband will be the murderer, expectations that have been shaped by the media: "The first half of Gone Girl is a nimble, caustic riff on our Nancy Grace culture and the way in which 'The butler did it' has morphed into 'The husband did it.'"[3] A New York Daily News review notes the novel's interest in how quickly a husband can be convicted in the media: "In a media society informed by Nancy Grace, when a wife goes missing, the husband murdered her. There's no need for a body to arrive at a verdict."[4] A San Francisco Chronicle review notes the book's recurring commentary on media influence: "Flynn pokes smart fun at cable news, our collective obsession with social media and reality TV."[5]
Characters in the novel are strongly affected by the Great Recession and the troubled economy. Flynn said that she wanted this novel to capture the sense of bankruptcy that both individuals and communities feel when the economy spirals. Not only have both her main characters lost their jobs, they have also moved to a town that is blighted by unsold houses and failed businesses. "I wanted the whole thing to feel bankrupt ... I wanted it to really feel like a marriage that had been hollowed out in a city that had been hollowed out and a country that was increasingly hollowed out," said Flynn.[6]
An underlying theme is feminism, most notably represented in Amy's "Cool Girl" speech. Despite her otherwise villainous character, this monologue has been praised for articulating the pressure that women face to morph into the male's ideal.[7] Flynn is a self-identified feminist and has stated that Amy's "just pragmatically evil" character and non-conformity to the traditional perception of women as innately good characters are the embodiment of feminism, which she defined as "the ability to have women who are bad characters."[8]
Amy's "Cool Girl" speech, and Nick's performing for his media spectators, highlight the importance of establishing and maintaining public appearances, however false. Flynn said: "The whole point is that these are two people pretending to be other people, better people, versions of the dream guy and dream girl, but each one couldn't keep it up, so they destroy each other".[9] Amy creates her plan to frame her husband when Nick fails to maintain the false image that Amy married, which she feels she is owed for keeping her side of the bargain by pretending to be his "cool girl" fantasy. She only returns to him after he gives a convincing public performance in the role of perfect husband. However, it is not his sincerity she is attracted to; she knows he is putting on an act, but the appearance of it. Amy views Nick as her ideal husband in the end because she knows he must appear to be her ideal husband, permanently, due to her blackmail and the risk of public condemnation. In exchange, she will appear as an ideal wife and mother, a trade which Nick accepts. Both prefer the appearance projected by the other over the reality of the person they married.
