Gone Girl is a 2014 American psychological thriller film directed by David Fincher and written by Gillian Flynn, based on her 2012 novel of the same title. Set in Missouri, the story is a postmodern mysterY that follows the events surrounding Nick Dunne (Ben Affleck), who becomes the prime suspect in the sudden disappearance of his wife Amy (Rosamund Pike). The film also stars Neil Patrick Harris and Tyler Perry.

DETAILED PLOT

On their fifth wedding anniversary, writing teacher Nick Dunne returns home to find his wife Amy missing. Her disappearance receives press coverage, as Amy was the inspiration for her parents' popular Amazing Amy children's books. Detective Rhonda Boney finds poorly concealed evidence of a struggle in the house. Suspicion mounts around Nick, whose apathy is interpreted by the media as characteristic of a sociopath and even sows doubt in his twin sister Margot.

In the past Amy revealed to Nick that Amazing Amy was a perfected version made up of the real Amy's failures. Their marriage disintegrated over time; both lost their jobs in the recession and moved from New York City to Nick's hometown of North Carthage, Missouri, to care for his dying mother. Nick became lazy and distant, and began cheating on Amy with Andie, one of his students, while Amy became increasingly resentful towards Nick for making her move with him to Missouri.

Forensic analysis of the house uncovers cleaned bloodstains, indicating a probable murder. Boney unearths evidence of financial troubles, domestic disputes, and Amy's recent willingness to purchase a gun. Medical reports indicate that Amy is pregnant, which Nick denies knowing.

Amy and Nick had played treasure hunt games on every wedding anniversary; this year's clues include profligate items purchased with Nick's credit card, as well as a diary highlighting Amy's growing isolation and ending with the fear that Nick will kill her.

Amy drives to a campground in the Ozarks. Upon discovering Nick's affair, she had concocted an elaborate plan to frame him for her murder and make his motive appear to be monetary. She fabricated a long-standing diary that was accurate in its early entries but later evolved into false accounts of spousal violence and her increasing fear of Nick. She had befriended a pregnant neighbor to tell her fake stories about Nick's temper, and steal her urine to fake pregnancy results, all while hiding the friendship from Nick. She planted corroborating evidence of Nick's guilt in the clue spots for the "treasure hunt" for the police to find. She also splattered her own blood across the kitchen, and cleaned it haphazardly. She anticipated that Nick would be executed for her murder, and planned to kill herself.

Nick deduces Amy's plan and convinces Margot of his innocence. He flies to New York City and hires Tanner Bolt, a lawyer known for representing men accused of killing their wives. Nick also meets Amy's ex-boyfriend Tommy O'Hara, whom Amy had falsely accused of rape, by planting evidence around his house. Nick approaches another ex-boyfriend, the wealthy Desi Collings, against whom Amy previously filed a restraining order, but Desi turns him away.

When Amy's campground neighbors rob her, she calls Desi for help, convincing him that she fled Nick's abuse. Desi agrees to hide her in his lake house. After Andie reveals their affair at a press conference, Nick appears on a talk show professing his innocence and apologizing for his failures as a husband, in the hope of luring Amy out of hiding. Boney believes she has enough evidence to arrest Nick for murder, but Bolt gets him out on bail. However, his performance rekindles Amy's feelings for him. She uses Desi's surveillance cameras to help make it appear that he kidnapped and raped her. She seduces him, murders him with a blade, and returns home to Nick covered in Desi's blood, clearing Nick of suspicion.

When Boney probes into the holes in her story, Amy chastises her as incompetent. The FBI sides with Amy, forcing Boney to back down. Amy tells Nick the truth and admits to Desi's murder, saying that the man she watched pleading for her return on TV is the man she wants him to become again. Nick shares this with Boney, Bolt, and Margot, but there is no evidence of her guilt.

Nick intends to leave Amy, but she reveals she is pregnant, having inseminated herself with Nick's sperm stored at a fertility clinic. Nick reacts violently to Amy's insistence that they remain married, but feels responsible for the child. Despite Margot's objections, he reluctantly decides to stay with Amy. The "happy" couple announce on a television interview that they are expecting a child.