Nellie Andreeva

UPDATE from Deadline’s TCA reporter Ray Richmond: AMC’s SVP original programming Joel Stillerman spoke briefly about the Walking Dead showrunner change at the top of the network’s panel for its upcoming period drama Hell On Wheels, which will premiere Nov. 6. (AMC’s official statement below). “I wanted to give a very heartfelt thank you to Frank Darabont, who is a visionary writer and director,” Stillerman said. “He wrote and directed a brilliant pilot, and we’re grateful for his contributions to the show.” He wouldn’t elaborate on the circumstances behind the change. “We’re excited to move on with Glen (Mazzara), that’s about all I’ll say on that.”

Stillerman also addressed the viewer outrage over the inconclusive Season 1 finale of The Killing. “I think the major takeaway for us is that we certainly would have taken a different approach to managing the expectations (of the Season 1 finale),” he said. “It was never our intention to mislead…We didn’t manage the expectations the way they should have been managed.” And he made a promise: “Viewers will definitely find out who killed Rosie Larsen in Season 2.” As for AMC’s flagship series, Mad Men, creator Matt Weiner and his team are breaking stories in the writers room for the upcoming Season 5 and writing scripts. Production starts on August 8, with Jon Hamm making his directorial debut on the first episode as previously reported.

PREVIOUS 8 AM: AMC, which hosts a TCA panel for its upcoming period drama Hell On Wheels this morning, just addressed the recent changes on its highest-rated series The Walking Dead, confirming that creator/executive producer/director Frank Darabont has stepped down as showrunner and that his No. 2, writing executive producer Glen Mazzara, has been elevated to the role. Here is the statement:

The Walking Dead’s Glen Mazzara, writer and executive producer, is expanding his responsibilities to assume the role of showrunner. AMC is grateful to executive producer, writer and pilot director Frank Darabont whose contributions to the success of The Walking Dead are innumerable.  We continue to discuss his ongoing role with the series.

Robert Kirkman, creator of The Walking Dead graphic novels, executive producer and writer on the series, will remain in this role and will continue to steward the brand.  Gale Anne Hurd will remain in her role as Executive Producer. The production continues on schedule for an October 16th premiere.

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