Amy Dunne stages her own disappearance
On her fifth wedding anniversary in North Carthage, Missouri, Amy Dunne vanishes and the evidence points to her husband Nick, who has been having an affair and lies to police. At the midpoint the novel reveals that Amy planned it herself: she forged a diary recording fear of Nick, planted clues, and faked a crime scene so he would be convicted of her murder. She later returns claiming she was kidnapped, and by announcing a pregnancy she binds Nick into staying in the marriage.
