Rust Cohle

On January 3, 1995, Detectives Cohle and Hart are assigned to investigate a ritualistic murder in rural Erath. They discover that the killer raped and tortured the victim, a prostitute named Dora Lange, and subsequently attached a pair of deer antlers to her head and posed her underneath a tree in a field.[2] They also discover strange stick structures that appear occult in nature. Cohle believes it to be the work of a serial killer. The murder becomes a local media sensation, attracting the attention of reverend Billy Lee Tuttle, cousin of the state governor, and together they seek to assemble a task force related to crimes deemed anti-Christian, much to Cohle's chagrin. During their investigation, Cohle and Hart gain access to Lange's diary, which contains repeated references to "Carcosa" and a "Yellow King". In the wreckage of a burnt-out church Lange attended, they find more structures and a painting on the wall depicting a human figure wearing antlers.[3]

Cohle and Hart work the case for three months, during which they trace the murder to Reggie Ledoux, a former Avoyelles prison cellmate of Lange's ex-husband, Charlie.[4] They learn that Reggie manufactures methamphetamine for an East Texas-based outlaw motorcycle club called the Iron Crusaders, whom Cohle has a history with from his time undercover. Cohle steals cocaine from the evidence lockup and meets with the Iron Crusaders while posing as a drug dealer representing a group from Mexico. Known to the bikers as "Crash", he reluctantly agrees to assist a group of them in a home invasion so the ringleader, Ginger, will lead them to Ledoux. Accompanied by Cohle, the bikers poorly disguise themselves as police officers and attempt to rob a drug house in an African American housing project, which results in a shootout leaving several people dead.[5] Cohle escapes and kidnaps Ginger, who takes him to meet Reggie's cousin and partner, Dewall. Dewall refuses Cohle's fake business offer, but Hart follows Dewall to their rural meth lab and calls Cohle to provide the location. Hart and Cohle discover that the Ledoux partners have kidnapped two children, and Hart executes Reggie in a fit of rage. Dewall is killed after he flees and blows up on one of his own explosive booby traps. Cohle stages evidence to support Hart's story that Reggie opened fire on them, forcing Hart to kill him in self-defense. The two are hailed as heroes, and receive commendations and promotions.[6]

Cohle in 2012

In 2002, Cohle interrogates a suspect who reveals that Reggie and Dewall did not act alone.[6] He tells Cohle that he will give them information about the "Yellow King" in return for a plea deal. Cohle wants to investigate this lead further, but the suspect suspiciously commits suicide in his cell that night after receiving a phone call. Cohle becomes obsessed with reopening the case, and pursues several leads, including a private Christian school run by Billy Lee Tuttle that had been closed amid rumors of child sexual abuse. Tuttle complains to Cohle's superiors, who suspend Cohle and order him to leave the case closed. That night, Hart's wife Maggie arrives unexpectedly at Cohle's apartment and seduces him as revenge for Hart's infidelity. Hart finds out and gets into a fistfight with Cohle in front of the entire department. Cohle quits the force the same day, and becomes a drifter and an alcoholic. He initially returns to Alaska and supports himself as a fisherman. Upon his return to Louisiana in 2010, he works as a part-time bartender.[7]

In 2012, a murder similar to the Lange case from 1995 occurs and Cohle is seen in the vicinity of the body, arousing the suspicion of LSP detectives Gilbough and Papania. They believe that Cohle may have been the killer in 1995 because he led Hart to every break in the case and seemed to know everything about the killer's frame of mind. They interview Cohle and Hart, who both refuse to cooperate once the purpose of the interview becomes clear.[7]

Cohle meets with Hart, who has also quit the police department and runs his own private investigation firm; he tells him that he has found evidence leading to the killer. Hart is skeptical and still resentful of Cohle for having sex with Maggie, but Cohle convinces him to help with the investigation by showing him a videotape he stole from Tuttle's home. The video is over twenty years old, and shows numerous masked men abusing and killing Marie Fontenot, a missing child whose name had come up in their investigation seventeen years prior. Cohle and Hart track down the original case's chief investigating officer, Sheriff Steve Geraci, and interrogate him at gunpoint. Geraci tells them that his superior, the late Sheriff Ted Childress, ordered him to halt the investigation; Childress was one of Tuttle's relatives.[8] They soon discover that the Tuttle and Childress families — to whom both Reggie and Dewall Ledoux belong — are related, and have long histories of child abuse and murder. They ultimately discover that the killer is a Childress, and go to the late sheriff's home to investigate.[9]

Cohle and Hart travel to the Childress house, where they find that the sheriff's son, Errol, is the killer. They discover the remains of his father tied up in a shed. They also encounter Betty Childress, his mentally disabled half-sister, with whom he is having an incestuous relationship. Cohle pursues Childress into the catacombs behind the house, which Childress identifies as "Carcosa". Cohle discovers an idol draped in yellow and covered in skulls — the "Yellow King" — and has a hallucination of a spiraling vortex, the same vortex that had been drawn on many of the victims. Childress stabs Cohle in the abdomen and also attacks Hart, but Cohle saves his partner by shooting Childress in the head, killing him. Gilbough and Papania, whom Hart had called, arrive at the scene. With the evidence Hart and Cohle collected, they connect Childress to dozens of murders, including Dora Lange's.[9]

Cohle falls into a coma, during which he feels the loving presence of his deceased father and daughter. He later wakes up in hospital and leaves with Hart, and looks up at the night sky, telling his partner, "Once there was only dark. If you ask me, the light's winning."[9]

Cohle also makes a brief appearance in season 3. He is indirectly mentioned when a news article from 2012 about him and Hart is seen on a computer screen showcasing their involvement in uncovering the murders committed by Errol Childress.[10]