Dark places, inhabited by unstable, unpredictable characters.
The main character, Libby Day, is 31 at the opening, a bitter, angry young woman not given to trusting others. Or even having others in her life. She's always been a bit standoffish but events in her early life sent her down a road of manipulation and guardedness.
At the age of seven, in early 1985, Libby was in the house when she heard others being attacked. Although she did not see anything, she head enough to make her afraid. She managed to slip out of the house and hide in the nearby woody area. She heard her brother Ben calling for her a little later but remained hidden.
Her mother and two sisters were killed that night: her mother was knifed, then shot in the head, her sister Michelle was strangled in her bed, and her sister Debby was axed to death. Libby herself stayed out all night, made it to a gas station to call for help, and ultimately lost two toes and a finger to frostbite.
Ben was charged with the murder, and in part because of Libby's testimony, he was sent to prison for life. Libby grew up with her aunt, the subject of much attention from the press, and at age eighteen inherited a large amount of money from collections made for her. In her twenties she was persuaded to co-author a self-help book, a pop survival book, but she herself didn't believe much that was in it.
At age 31 she learns she is almost out of money. Getting a regular job just seems too much to her. She feels too tired and she doesn't get along well with others. So when the opportunity to earn a little money by talking to a group of "murder fans" comes along, she takes it. She meets this odd assortment in an old building, where they are split into interest groups - interest in various sensational murder cases. Her case draws interest because many people believe Ben to be innocent. They want to locate the real killer.
Eventually, although she is upset to find that everyone in the group believes Ben to be innocent and her to be complicit in his conviction, she comes up with a plan to get more money from them. She will talk to various key players in the episode, ask them questions that possibly only she can ask. And thus she sets off on a journey that takes on a life of its own.
The chapters alternate between 1985 and "now". Libby's chapters are in first-person, the others in third. Gradually we creep up on the actual night of the murders, inch by inch, through the experiences of Ben, Libby's mother Patty, and a few others, with breaks for Libby's current travels. The technique builds suspense to the point where I found it almost unbearable to go on. Or to not go on.