Season synopsis
Contains spoilers for this season and earlier seasons.
Louisiana detectives Rust Cohle and Marty Hart investigate Dora Lange's murder, finding her body arranged beneath a tree with antlers and twig figures. The inquiry leads toward missing children, religious schools and powerful members of the Tuttle family. Years later, other detectives question the former partners separately about that investigation. A similar killing has raised doubts about the men they blamed and about Cohle himself.
In the original case, Cohle uses old undercover contacts to reach Reggie Ledoux's drug operation. Hart finds abused children and shoots Ledoux; his accomplice dies in a trap. The partners stage a gunfight and receive credit for solving the case. Later evidence convinces Cohle that the killings continued. His investigation and Hart's renewed infidelity deepen the damage at home, and Maggie's encounter with Cohle leads to a fight that ends the partnership.
The two eventually reunite, confronting evidence of Marie Fontenot's murder and a wider cover-up. Hart connects a witness's description of green ears to a freshly painted house, leading them to Errol Childress. Cohle follows him into Carcosa's tunnels, where both detectives are badly wounded before Cohle shoots him dead. They survive, and bodies recovered from the property establish Childress's crimes. The larger network escapes full accountability. Outside hospital, Cohle describes feeling his lost family's love during his coma and finds a reason to see hope.