Amy was born into a privileged family, the daughter of two emotionally codependent writers who had previously suffered from several miscarriages. Her parents Rand and Marybeth used her as the inspiration behind their highly acclaimed book series, Amazing Amy. Although Amy was a beautiful, smart, charismatic child, this perfect character always outshone her. No matter what she did, “Amazing Amy” did it better.  

Growing up in the shadow of this fictional version of herself, Amy develops identity issues and an insatiable need to be the most cherished person in every room she’s in. She’s meticulous and detail-oriented, which allows her to plan and execute elaborate schemes to punish others without ever getting caught. Indeed, while she appears charismatic and charming on the surface, it’s all an act, as she calibrates her personality to best fit the company she keeps. Throughout her life, she forms intense friendships and romantic relationships. Then, when she tires of her companions, she ruins their lives, always providing them with untraceable evidence that she is the one responsible. When she meets Nick Dunne, she finally feels that she has found her equal, and is able to crawl out from underneath the shadow of “Amazing Amy” and be loved in her own right. However, when she finds out that Nick is cheating, her old instincts to take revenge on those who have wronged her become too strong to resist. She feels that Nick has ruined her life by forcing her to move to Carthage, by spending all of her money, and becoming a boring and unworthy partner for her. Amy's disappearance on her fifth wedding anniversary—and the detailed diary entries she fabricates to paint Nick as a monster— are a carefully planned act of revenge for all of these failures. 

Amy is a mastermind at planning the destruction of other peoples’ careers and relationships. She manipulates public perception of herself and Nick, figuring out how to puppet-master her neighbors and bamboozle law enforcement. Amy takes a very cynical view of other people’s intelligence. She’s also skeptical of equitable relations between genders, as men have objectified her whole life. She sets things in motion and then retreats, watching everybody scramble from a safe distance as she delights in how clever she's been. However, towards the end of the novel, when she sees that Nick is capable of pretending to be the husband she wants him to be, she decides to return to him. Although it seems as if she might have unwittingly fallen victim to the schemes of Desi Collings, who was the only one of Amy’s former lovers to be truthfully obsessed with her, she quickly rids herself of him and makes it back to Carthage. When she gets home, Amy claims to be a kidnap victim, further manipulating her situation so that Nick is forced to take her back. Her final actions in the novel (the fake pregnancy and the openness with Nick about her lying and her expectations of his behavior) are all to ensure her control over her narrative and her life. In short, Amy is a sociopath, a murderer, and an expert at everything she tries.