The Walking Dead season 9 will see Negan in a very different frame of mind according to actor Jeffrey Dean Morgan. Set to premiere on AMC next month, The Walking Dead's forthcoming season is set to be a landmark run in the show's history with lead actor Andrew Lincoln due to depart. Season 9 will also introduce new villains The Whisperers, as well as a number of new protagonists and a time-skip that will take the show a couple of years into the future, by which time Alexandria and its allied communities are thriving.

One character not exactly thriving is the beaten leader of the Saviors, Negan. At the end of last season, Rick finally managed to defeat the brutal dictator but made the controversial decision to keep him alive, a decision that could trigger civil war among Rick's group. Instead, Negan will be forced to watch Rick's community grow and flourish in season 9 and one might think that his new status as a prisoner of Alexandria would curb Negan's tendency for colorful insults and rambling speeches.

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According to Jeffrey Dean Morgan however, that's very much not the case but beneath the surface, Negan's isolation is set to drive him insane. Speaking to various media outlets including Screen Rant during a set visit, Morgan stated:

"That [Negan's typical dialogue] doesn't go away.Whenever I see that I'm in an episode, I promise you, it's 42 pages of dialogue. With the exception of maybe episode 2. I think what has been interesting this year, for me, is that we're seeing Negan vulnerable... I don't think anyone interacts with him, except for possibly Rick... I think Negan probably lives for that. I think that's all he thinks about, 'Please Rick, come down here.' And so I think that is when he gets a little bit of bravado.

I think he's going insane. I think the four walls have closed in on him, so he's battling trying to keep some sense of sanity. And it's not going well. He's used to performing in front of a lot of people and putting on a show. Unable to do that, kill the party, is very important to his psyche. He's going through a lot sh*t right now."

One of the things many The Walking Dead fans love about Negan is his unique way with the English language and it's reassuring that his incarceration won't put an end to this popular feature of the character. What will be very interesting, however, is how losing his position of power will alter Negan's personality and mindset, with viewers fully aware that any outward bravado is merely a facade to cover his fragile mental state.

One big question heading into The Walking Dead season 9 is how long Negan will physically remain within his cell. Realistically, there's only so long the show's producers will want to keep the character cooped up in the same room, only interacting with a handful of people. Exactly how and for what purpose Negan will be released could be a major factor in the forthcoming arc.

Indeed, Negan could end up being one of the most pivotal characters in The Walking Dead season 9. With Rick set to depart, the show will be in need of a central leader figure. While Michonne would certainly be a potential candidate for this position, Negan also has the charisma and leadership skills necessary to fill the void created by Rick's departure and although he committed some unspeakable acts during his two seasons on-screen thus far, the The Walking Dead comic books have actually seen Negan make steps towards being more of a protagonist.

More: The Walking Dead Season 9 Premiere Review: A New Era Begins Now

The Walking Dead season 9 premieres October 7th on AMC.