Dark Places is a 2009 mystery thriller novel by American author Gillian Flynn. The narrative moves between two time periods, 1985 and 2009, as the protagonist, Libby Day, tries to solve her family’s brutal murder. The novel deals with the consequences of the 1980s Satanic Panic and the fallout from the 1970s Farm Boom for a community in the rural Midwest. Flynn is the author of Gone Girl (2012) and other popular mystery thrillers.

Dark Places garnered many awards. It was a New York Times bestseller, a Best Book of 2009 for Publishers Weekly, and The New Yorker’s Reviewers’ Favorite Book from 2009, among other accolades. The novel was adapted into a film starring Charlize Theron in 2015. This guide uses the eBook published by Crown in 2009.

Content warning: The book includes scenes of graphic murder, violence against children, Satanic worship, and references to addiction, death by suicide, and child molestation.

Plot Summary

Protagonist Libby Day, 31, is the only survivor of a horrific murder in which her mother, Patty, and two sisters, Michelle and Debby, were killed. Her brother, Ben, was convicted and is serving a life sentence. The murders occurred when Libby was seven, and the public created a donation fund that was released to her when she turned 18. Now, the fund is running out, and Libby has no other income.

A man named Lyle contacts Libby on behalf of his Kill Club, a true-crime group dedicated to solving her family’s murder. They believe Ben is innocent and that Libby’s eyewitness testimony is false. Lyle pays Libby to investigate the murder, and the story unfolds as Libby revisits people and places from her past in search of the truth.

The chapters alternate between present day (2009) and January 2, 1985. All of the present-day chapters occur in Libby’s first-person past-tense point of view, with the exception of Chapter 42, which follows Ben. The 1985 chapters alternate between Patty and Ben and are written in limited third-person past tense. Chapter 40, which takes place in 1985, follows one of the murderers, Calvin Diehl.

First, Libby contacts Barb Eichel, a former reporter who wrote a book about the murders in 1986. In the book, Barb plays up Ben’s involvement in Satanic worship, but when Libby meets her, she apologizes. She had been caught up in the Satanic Panic of the time and no longer believes Ben is guilty. Barb believes Libby was coached to provide damning evidence against Ben. Libby is not ready to believe this because it would mean she is guilty of putting her innocent brother in prison for life.

Next, Libby visits Ben in prison. It is the first time she has seen him since the murders. Ben is happy to see Libby and absolves her of blame; like everyone else, he could see she was coached. When Libby presses him about why he didn’t provide a better alibi, he says he wanted to look tough. After their meeting, Libby is sure Ben is innocent.

Libby searches for her neglectful father, Runner, as a possible suspect. He had gambling debts, which Libby thinks could have been a motive. Runner lives in a halfway house in Oklahoma, but he is not in when Libby calls. Libby calls her aunt Diane, who raised her for a while, but Diane does not call back. In between visits, Libby talks with Lyle about the case. Together, they go to see Krissi Cates, a girl who accused Ben of sexually molesting her when she was 10. Lyle suspects her father could be the murderer.

Krissi, unaware of who Libby is, claims that Ben molested her as part of a Satanic ritual. Libby leaves her name and address, and Krissi shows up later to apologize. She admits that she lied about Ben and says that by the time the murders occurred, her father no longer suspected Ben of molesting Krissi.

Libby and Lyle visit Magda, a member of the Kill Club who heads a group dedicated to getting Ben out of prison. She pressures Libby to officially recant her testimony. Runner’s former girlfriend is part of the group and tells Libby that she lied to the police: She said Runner was home with her all night, but he was out until almost dawn. Magda’s group funds Libby’s trip to Oklahoma to find Runner.

Libby visits Ben again, and he is angry that she is interrogating him. She asks who Diondra is; Libby found an old note from her implying Ben was her high school boyfriend. Ben says he never knew Diondra, but Libby suspects he is lying. By this point, the reader knows through the 1985 chapters that Diondra and Ben were dating, which makes Ben’s lie suspicious. Libby visits Runner, but he is unhelpful. Libby concludes that he is not guilty because he is not smart enough to pull off a murder without getting caught.

The truth of the murders unfolds in the chapters from 1985. On the morning of January 2, Ben leaves the house after dyeing his hair black the night before. Patty is worried about Ben: Lately, he wears all black, constantly talks on the phone, and has a padlock on his bedroom door. This is uncharacteristic of Ben, who is a loner; Ben keeps Diondra a secret, so Patty does not know he has a girlfriend.

Patty has difficulty raising her children. Runner does not pay child support and only comes around when he needs money for his gambling debts. On January 2, the bank forecloses on Patty’s farm, and Patty learns that Krissi Cates has accused Ben of sexually molesting her. Patty and Diane can’t find Ben, and Runner comes to the house to demand money. Meanwhile, Ben is drinking with friends of Diondra’s cousin, Trey. Ben, angry about being bullied, lies about helping Trey with Satanic sacrifices. Trey arrives and takes Ben to see Diondra. Diondra is pregnant with Ben’s child, but she smokes and drinks anyway. She tells Ben they have to run away so her parents won’t find out she is pregnant. That night, she and Trey pressure Ben into getting high and participating in a Satanic ritual. Afterward, Diondra and Ben go to Ben’s house to get money, where Diondra strangles Michelle for threatening to reveal Diondra’s pregnancy. The murders of Patty and Debby also take place. When the unknown murderer leaves, Diondra mutilates Debby and Patty’s bodies with an axe. In the morning, she and Ben return to contaminate the crime scene.

In the present, the only person of interest left is Trey. In addition to being Diondra’s cousin, Trey was a bookie to whom Runner was in debt. Trey says he had nothing to do with the murders; in fact, they scared him into getting clean and stopping his Satanic worship. Trey does not have any current information about Diondra, but he knows she used to use the pseudonym Polly Palm.

Libby finds Diondra in a remote area of Kearny, Missouri. She welcomes Libby and introduces her to her daughter, Crystal, who is Libby’s niece. During their conversation, Libby begins to suspect Diondra of the murders, and Crystal knocks her out with an iron. Libby manages to escape and calls Lyle in the morning.

After picking up Libby, Lyle tells her that the man who murdered Debby and Patty has been caught. Since the 1980s, a man named Calvin Diehl has helped people stage their deaths so their families can inherit their insurance money. Calvin gave the police letters his clients wrote admitting that they paid him to kill them, and Patty’s letter is among them. Calvin admitted to killing Debby, who walked in during Patty’s murder.

With the cases solved, Ben can get out of prison, and Libby can move on with her life. Libby reconciles with Diane and develops a real friendship with Lyle.