What a phenomenal ending. I know that some people thought it too tidy, but the beauty of it lies in the simplicity. There are so many different nuances and layers to the show, and it takes your mind in a million different directions. Surreal aspects like the Lovecraftian references and Rust's hallucinations let your imagination run wild with possibilities that all of this might not be as "grounded" as we think, visual cues and red herrings like Marty and the Pasta are used to empower our cynical side; what if it is all darkness? What if this force has corrupted the guys we're supposed to be rooting for, but, what I love about the finale is that it cements our role as Rust.
He's our perspective character. I've made no secret of how relatable I found him, but, when we look at our lives, we all have the same feelings that Rust has, at some point or another. We're infected by rationalization, doubt, and cynicism, and uncertainty; we're uncertain of our importance, out existence, our role in the universe, and it will always be ambiguous, but, and maybe I'm wrong here, as I said, the beauty lies in the simplicity of it; light versus dark. We can choose to let those feelings consume us, or we can choose a different path. That warmth that Rust felt; his daughter's love, again. You could choose to look at it as "Rustin Cohle" finally seeing the light and knowing that there's more than this life, or you could see it as a reignited faith in life. After everything he's been through, after all of the cynicism; you see that Rust has hope in his existence, for the first time since the show's started; he chooses to embrace the light, and cast out the darkness.
I've talked non-stop about this, but I can't help it. True Detective is unlike anything I've ever seen before, and I question whether I'll see anything like it ever again. Not to mention, it features what I feel are two of the best performances of the respective leads' careers; film or otherwise.