AMC's The Walking Dead will close out its third season Sunday with the final episode overseen (and written) by departing showrunner Glen Mazzara.

Mazzara first joined Walking Dead during season one, contributing freelance scripts to the zombie drama. He took over showrunning duties from the since-departed Frank Darabont -- who adapted Robert Kirkman's comic series -- midway through the show's second season. In that time, Mazzara's accelerated storytelling approach has earned both critical praise and record-breaking ratings, with the series ranking as the No. 1 show across cable and broadcast in the advertiser-coveted adults 18-49 demographic. Among total viewers, Walking Dead averages more than 11 million total viewers per episode.

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In addition to the series' pacing, Mazarra has added new characters in the Governor and Michonne, two favorites from the Kirkman comics on which the AMC series is based.

"He's done a fantastic job and the testament is on the screen. It's been brilliant working with him. He's the man who cast me and brought me into the show, I have great love and affection for him," David Morrissey, who plays the Governor, said of Mazzara. Added Danai Gurira (Michonne): "I love Glen and I know he's an amazing showrunner and will continue to be one in the future on many different realms and ways. I wish him all the best."

Mazzara, however, is already looking to his next act. In fact, he recently signed an overall development deal with Fox TV Studios, for whom he once worked alongside Shawn Ryan as a writer and executive producer on The Shield years earlier. As part of the new arrangement, Mazarra is expected to develop cable projects for the News Corp.-owned studio.

The move comes some three months after Mazzara announced jointly with AMC that he would be exiting Walking Dead, citing creative differences. He indicated at a January conference that he didn't have the authority that his role as showrunner role would imply. "When you’re the creator, you can say, 'This is what the show is,' " he said at NATPE. "I didn't create the show. I didn't create the comic book, so I'm just glad I was able to contribute." (Scott Gimple, who joined the series during season two, will take the helm when season four returns for its likely October bow.)

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Executive producer Gale Anne Hurd, who has been with Walking Dead since Day 1, had nothing but good things to say of her experience working with Mazzara. "He has been fantastic and a great collaborator and I know he's going to continue to have both commercial and critical success," she noted.

Star Andrew Lincoln, whose beleaguered former sheriff Rick Grimes is the focal point of the series, got emotional when asked to share parting words for Mazzara. "I've said everything I needed to say to him in private. It's too difficult a question for me to answer," he told THR. Steven Yeun (Glenn) was far more willing to weigh in when asked: "I love Glen. He worked his ass off for our show and whatever it is, it is," he said, adding: "Thank God I have no control over that stuff otherwise I would be beating my head in. But much love to Glen. He's a jolly person with great stories. Just the fact that he's willing to listen to every cog in this giant machine says leaps and bounds about him."

For his part, Mazzara used the WonderCon stage Saturday to bid farewell to the series. "What's been great about The Walking Dead is, it's really been the holy grail of storytelling," he told fans during a genre showrunners panel at the annual Anaheim convention. "To find work that connects with people on such an emotional level isn't something I take lightly. Hopefully I can do that again with some future show. To connect with an audience that has been so passionate has been a wonderful experience and I thank everyone for that; it's meant a lot."

The Walking Dead's season three finale airs Sunday at 9 p.m. on AMC.

Email: Lesley.Goldberg@thr.com; Twitter: @Snoodit