True Detective spans 17 years, follows the relationship of two men working on a ritualistic murder case and features one of the most complex, haunting and intriguing characters in TV’s recent history: Rust Cohle, played masterfully by recent Oscar winner, Matthew Mcconaughey.

Matthew McConaughey as Rust CohleMatthew McConaughey as the 2012 Rust Cohle from episode three

For his role as Ron Woodruff in Dallas Buyers Club, McConaughey lost 50 pounds, something he said made him acutely aware of what was around him; he was hyper alert He couldn’t get sunlight, couldn’t eat anything outside his controlled diet, and when he found out exercise wasn’t aiding his weight loss, he – in his own words - became “hermetic”.

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With this kind of dedication to the characters he plays, it should come as little surprise that he studied the complex role of Rust, especially given the extended time allowed to him by the medium of TV to develop the character, and the intrinsically multifarious nature of the troubled homicide detective.

This obsession with his character’s folklore manifested itself in the form of a 450-page graph, which maps out the coke-addled, substance abuser Cohle from the work-obsessed, existential-mumbling, dangerously cynical and maverick vigilante Cohle. He brought his homework along to show Rolling Stone in an interview. So here, in McConaughey’s own words, are the four stages of Cohle. Three of them we see in the show; the other - "Crash" - helps flesh out Cohle's enigmatic past. 

1995 Cohle

"Back to being a part of the body. He's coming off of years being Crash. He's trying to walk the line. Monk-like. Trying to hold it together. And that's a lot easier with less interaction with others. There's a mechanical side to him. He needs the regimen of the homicide detective. He needs the case to actually survive. One, because he's great at it. And two, because it's going to keep him from killing himself."

Rust Cohle True Detective1995 Cohle forensically flicks through case files to solve the case

Crash

"He's our deep, narco wild-ass. A guy who goes all the way. This is where Cohle has all the freedom. He can go over the edge as this guy. And inside, he loves the life of Crash even more, because the shackles are off of him. He knows he may die sooner living this life, but there's a freedom and peace in that knowledge for him."

2002 Cohle

"A little looser mix of Crash and the '95 Cohle. A guy who's made his boundaries clear and has to mark less territory, so he's relaxed into his way in the world. But the case is still his lifeline. He has some small hope that there's going to be a way out of his being and pain and criticism, so he makes an effort into domesticity, a la the girlfriend. Only to prove that he was not made for it, and there is no way out. So what does he do? He resigns to his nature, once again."

2012 Cohle

"This guy lived longer than he hoped. Fallen prey to his own beliefs. More cynical, angrier, he's had to endure the existence of this shitstorm called life. A little ragged, more rough edges, living in a place where he can manage himself. Not too close. He's not in the CID. But he's not in Alaska. He's a guy who's resigned to his indentured servitude of being alive. But he despises the sentence and the penance. He will not accept defeat. He's not going become a madman, he's not going to kill himself. He wrestles the devil every day, and he realizes that this may last a lot longer than he ever hoped for."

Woody Harrelson and Matthew McConaugheyWoody Harrelson and Matthew McConaughey as Marty and Rust follow up some leads

This Sunday marks the finale of what has been a triumph for everyone involved; True Detective’s pacing, direction, writing plot and acting have all excelled with the separate disciplines subscribing to genre tropes in the right places and treading new ground in others. Together they have formed one of TV’s finest dramas: a cop procedural-turned-psychological thriller-cum-all out character interrogation.