'American Sports Story's' Josh Rivera on the disease that contributed to Aaron Hernandez's downfall

LOS ANGELES -- The FX mini series "American Sports Story: Aaron Hernandez," executive produced by Ryan Murphy, is coming to a close with a dramatic finale.

The tenth and final episode follows Aaron Hernandez on the verge of a second trial, which stands to offer unexpected hope, but Aaron struggles as his deepest secrets weigh heavily on his mind.

On The Red Carpet spoke to the stars of the series, Josh Rivera (Aaron Hernandez) and Jaylen Barron (Shayanna Jenkins), and the creator of the show, Stuart Zicherman, about the season finale.

Zicherman explained the writing team's approach.

"We listened to the prison tapes," he said. "We wanted to, you know, explore this notion of life, does he feel any remorse?"

He went on to say, "I think that when you do experience remorse, all the things come up for you, you know, all the things have been issues. They all rise to the surface. And so, we tried to sort of like, bring them all back to a boil."

As Aaron navigates life in prison, the series investigates the factors that impacted his story, including a posthumous diagnosis of chronic traumatic encephalopathy (CTE), a neurodegenerative disease linked to repeated head trauma.

Rivera explained the role that CTE played in Hernandez's story.

"We had all of these things sort of foreshadowing the headspace, particularly chemically what was going on in his brain throughout, and we're kind of at this point of the endgame of what that looks like," he explained.

As for playing the part, Rivera researched by watching videos and trying to understand the way Hernandez's brain was making decisions.

"People can assume they have CTE. It can be likely, but it's not confirmed until after death... So that gave me a real sense of what that fear must be like to know that something's wrong, but to have no idea what it is, or you can suspect that something's going on. I mean, there's a real paranoia that comes with that, and it's just this kind of aimless unease."

He tried to approach the role with a certain level of humanity. "I really try to put humanity first... Nobody's born evil. Like, everybody, like, has a story or has a why or has some sort of context, which is not to explain or excuse anything away, but that is there... You know, life is not so binary, like good and evil. It's not so cartoonish like that, you know, it's complicated."

Barron approached her character in a similar way, saying, "It's difficult to not connect with her (Shayanna). It's difficult to not connect with Aaron. And it's difficult to not connect with Odin."

Watch the finale of "American Sports Story: Aaron Hernandez" Tuesday, November 12 at 10 p.m. on FX and streaming the next day on Hulu.

The Walt Disney Company is the parent company of FX, Hulu and this ABC station.