True Detective: “The Secret Fate of All Life” (Episode 1.05)

The answer is there. Have you figured it out?
When you really look at the evidence, it’s obvious. The concept of True Detective’s “Yellow King” is derived from the Robert W. Chambers’ 1895 short story collection The King in Yellow. It’s often cited as a huge influence on H.P. Lovecraft, and the title refers to both an evil supernatural entity and a two-act play that condemns its readers to insanity. Chambers also writes of a city called Carcosa, which is the dim, lost metropolis where black stars rise; to True Detective writer Nic Pizzolatto, it represents the domain of the Yellow King. From Chambers, we have our demon spirit, and we have our vessel. And before Martin Hart kills Reginald Ledoux in a blind rage for murder and kidnapping and unfathomable evil, the killer has a message for Rust Cohle: “You’re in Carcosa now … with me. He sees you.”
And though the line is omitted in “The Secret Fate of All Life,” Ledoux says in the clip linked above that Cohle, too, is a priest—a messenger for the Yellow King who will visit this place again because time is a “flat circle.” Cohle scoffs, but it’s a piece of philosophy he’ll echo 17 years later in an interrogation room as he stands accused of the same crime for which Ledoux gave his life. It’s a spiritual act of transference; when Ledoux dies, the Yellow King leaves his body and enters Cohle. The actions of the world cycle back upon themselves, and self-determination is an illusion for those who can’t recognize that fate has made them a prisoner. There is no independence. There’s not even death as we know it, just a presence that “created time to grow the things that it would kill.” For people, there’s only rebirth, and forgetting, and repeating. So Cohle becomes a servant to the Yellow King. He murders, and he covers up, and he coerces an armed robber into committing suicide when the man subtly threatens to expose him in an attempt to barter down from a life in prison. And it all began with Ledoux, who was nothing more than a body that had been inhabited; Cohle caught the madman, but he inherited the madness.
Or:
It happens later. The transformation is gradual, not immediate, the way a virus decimates a body. Guy Leonard Francis, the armed robber who confessed to Cohle that he killed two pharmacy workers in Livingston, implies that the Yellow King still lives, which is a thought that has plagued Cohle since his partner murdered Ledoux. Cohle has made every effort to live a normal life, even dating a doctor who is sufficiently attuned to his psychological eccentricities to say things like, “he’s conflict-oriented, so when I deny him small arguments, it builds up his energy.” But his eyes are hollow in the trappings of domesticity, and finally the pretense must fail.
A storm has been gathering in his mind for years, and it’s ready to rain. When he tells his interrogators that “someone once told me time is a flat circle,” we know that that someone is Ledoux himself, and that Cohle has been fixated on his words for 17 years—turning them over in an ongoing, obsessive analysis, and finally arriving at his own interpretation. He is consumed, and at the end of the episode, we see the moment where consumption gives way to seduction. He visits the abandoned school he had nearly entered years before, and in the gloomy interior finds the devil nets that are the sign of the Yellow King. He protects himself with gloves—one last attempt to distance himself from the malignant spirit that has been his destiny—but when he holds one up to a shaft of sunlight streaming through the window, he is enraptured. His soul is forfeit, his soul is transformed. He is a priest for the Yellow King.
Or:
Cohle meets Guy Leonard Francis in 2002, and knows by his use of the words “the yellow king” that this is no false offering. Ledoux is dead, but Ledoux was not at the top of the hierarchy. The man who turned him into a vessel is still alive and unaccounted for, and he is still killing. Cohle quits his job (or gets fired?), and either begins the hunt for the Yellow King, or attempts to flee.