We have several months left to go before The Walking Dead returns for Season 5. Many fans are wondering when the iconic comic book villain Negan will be featured on the hit AMC series. Executive producer and comic book creator Robert Kirkman reveals in an interview with MTV that he is constantly discussing Negan casting possibilities with showrunner Scott M. Gimple, teasing that he will likely end up on the show at some point, but not anytime soon.

"As far as Negan casting goes, Scott and I are always talking about who we would put in that, it's definitely on our minds, and there are definitely a lot of candidates. But I wouldn't expect Negan too terribly soon, although he is definitely in the plan. It's a 99% lock that he's going to be in the show eventually, so be on the lookout for that."
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Back in December, the executive producer revealed that Negan was not slated to appear in the second half of Season 4. In the comic books, Negan is the leader of a group known as The Saviors, who is responsible for the deaths of several characters and wields a baseball bat wrapped in barbed wire. When asked about the possibility of casting Mad Men star Jon Hamm as Negan, since his show is heading into its final season, Robert Kirkman said he would be perfect for the role, but they don't think they can get him.

"He's not tall enough! That's a joke. I think Jon Hamm would be perfect. I think after Mad Men has run, Jon Hamm is going to have a Tom Hanks level film career, so I don't think he'll be coming back to television anytime soon. Although that would be cool!"

Robert Kirkman also spoke about plans for Season 5, which begins production next month. He revealed that he has turned in the script for the season's second episode, and that they have already planned out the story arc, including the season finale.

"I think Season 4 is the strongest of the show so far, and I think Season 5 is going to continue that trend. I just turned in the second episode script for Season 5, and all the writers are hard at work on their individual episodes. We're pretty much halfway through the fifth season, script-wise. And we've already nailed down what our finale is, and what our overall arc of the season is. The back half of the season is taking shape very quickly, and we'll have all the scripts written by the summer. It's always interesting the way these things overlap. By the time people have seen the entirety of the season, we're already pretty much done with the writing on the first half of the next season. We're always quite a bit ahead. We'll be rolling cameras in May, so I'm very excited about that. We'll have another season of The Walking Dead down. It's strange for me, being on the fifth season, because I feel like we just started. Five is... On some shows, on some great shows, they run for five seasons and they're done. And it's like, 'Wow, that show ran for a long time.' I feel like we're still very much getting started, which is the feeling I've always had on the comics. So that's definitely a strange thing to realize, that five years have passed already."

AMC also announced in September that Robert Kirkman is developing a spin-off series, set to debut in 2015. While he wouldn't divulge any specific plot details, he is actively working on the story with showrunner Dave Erickson.

"As far as the spin-off goes, I'm actively working with [Showrunner] Dave Erickson on that, and we know when our proposed release date is - although I can't tell you that, obviously. We're working towards that show, and it's gonna be awesome."

Are you more excited for Season 5 of The Walking Dead now? Do you think Negan should be introduced this season? Chime in with your thoughts below.