'Robot Chicken' preview: 'The Walking Dead' special creators talk Negan's dip, Michael Rooker's singing, and guest Daniel Radcliffe

To celebrate the Oct. 22 Season 8 premiere of The Walking Dead — the series’ 100th episode — Yahoo TV will be posting a new TWD-related story every day through the season opener.

Longtime fans of Robot Chicken probably won’t be surprised, but The Walking Dead devoted, especially those still sensitive about the brutal death of Glenn in Season 7, might find it difficult to believe that there is comedy to be spun out of Mr. Rhee’s final moments, in which, brain damaged by Lucille’s swings, he tells Maggie, “I will find you.”

In The Robot Chicken Walking Dead Special: Look Who’s Walking, which premieres on Adult Swim on Oct. 8, Glenn does indeed find Maggie, in a skit called “Happy Glenndings.” And without spoiling the particulars of the comedy, we’ll just say that Glenn’s final words are oft-repeated, and they also form the narrative for his post-Negan attack life with Maggie in the sitcom-within-the Robot Chicken special.

“I’m biased because I wrote it, but ‘Happy Glenndings’… that’s just one of those things we do on Robot Chicken: What happened after everybody went home?” Clueless actor Breckin Meyer, a voice actor and Emmy-nominated writer for Robot Chicken, tells Yahoo Entertainment.

“[The special] is just this ultimate kind of love fest of The Walking Dead, of ‘Hey, let’s put this in, oh, we got to have Carl doing this, we gotta have Darryl’s crossbow, and Carl’s hat!’” Meyer says. “All of that. I think that was just the ultimate love letter to The Walking Dead.”

Robot Chicken’s homage to TWD came about after a suggestion by Walking Dead creator Robert Kirkman. “I wish it were a more elaborate story. At San Diego Comic-Con, I do this annual dinner with a bunch of people… We all kind of started in comic books, and Robert Kirkman is one of those people,” says Matthew Senreich, who created Robot Chicken with actor Seth Green. “So we were sitting there during our annual dinner, and [Kirkman] was like, ‘Hey, you’ve done these DC specials for Robot Chicken, why don’t you do a Walking Dead?” And I was like, ‘OK.’ So, really, it was very casual, and we just kind of joked about it at that dinner.”

Says Seth Green, “That’s a testament to both AMC and Adult Swim and how well they play together, that we were able to pull something like this off.”

“It was just about holding hands and, yeah, we just had a good time ever since,” Senreich says. “It’s the same way that some of our other specials came about, where we’re just playing with friends.”

The special’s origins story may not be elaborate, but the episode itself is, with a plethora of TWD nods everywhere you look. The story begins as a group is touring a Walking Dead museum, filled with artifacts like Daryl’s crossbow under glass and a talking make your own bullet machine featuring Eugene. A guide shares a warped version of apocalyptic history, until an older man wearing an eye patch – yep, Old Man Carl – appears and tells his version to a Robot Chicken regular: The Nerd.

Old Man Carl, as well as younger Carl, is voiced by TWD star Chandler Riggs, who’s joined in the special by co-stars present and past, including Andrew Lincoln, Norman Reedus, Jeffrey Dean Morgan, Sarah Wayne Callies, Jon Bernthal, Lennie James, Steven Yeun, Scott Wilson, Danai Gurira, Melissa McBride, Michael Rooker, and Josh McDermitt.

Both Green and Senreich say Lincoln may have enjoyed recording his lines for the special the most, as he fully embraced everything, from Rick’s scenes with a frisky unicorn to Rick’s attempt to come up with a new name for his group of friends and family.

“I watched Andrew Lincoln having what I thought was the best time ever,” Green says. “Because Rick Grimes is an incredibly serious character, and the work that Andy’s done on the show is unparalleled. He’s such an incredible dramatic actor, and the range of emotion that he’s covered over the course of the show, it’s just unbelievable. And so him bringing that same commitment and intensity for a comedic version of Rick Grimes was nuts. And he’s so good at it, he’s just throwing himself into this stuff, punching himself in the chest, and really doing the physicality as he’s recording. Like Rick pitching names for their group… the seriousness with which he did it, it’s the same as, you know, him defining the new laws of Alexandria.”

Adds Senreich, “It was fun trying to watch him straight face himself after he would record certain things because he’d make himself laugh doing it.”

Another highlight of Look Who’s Walking: “The Negan Dip,” a song-and-dance ode to one of Jeffrey Dean Morgan’s most standout acting choices for his portrayal of the bat-swinging baddie. Robot Chicken director, writer, and voice actor Tom Sheppard penned the song — teased in the trailer above — which was also inspired by another TV character.

“I felt like it needed to be like a bad pop song from the ‘60s that would’ve been on American Bandstand or something, where they really just try to cash in on somebody’s catchphrase or mannerism,” Sheppard says. “There was an old video we found of Lurch [Ted Cassidy] from The Addams Family doing a song on some ‘60s TV show called “Do The Lurch,” and that played a big part in shaping this thing.”

Senreich says Morgan got a kick out of the tune when he Skyped in to record his lines for the special. “He said to us that he didn’t even realize he was doing that until the third day. Then he realized that once he’d committed to it, he was like, ‘This is going to be part of my character.’”

And then there’s Michael Rooker, who actually sang Merle’s song about hoping to find love with someone who feels the same way he does about the opposite sex and race.

“Well, I do love that Negan song, but my favorite sketch is that love song Merle sings before meeting his true love,” Sheppard says, laughing at the memory of Rooker protesting when he was asked to sing it. “It’s completely unexpected and crazy and yet somehow poignant at the same time. I kind of felt like he could [sing], but we were still pretty shocked. He came in with a lot of excuses about what we were about to do, and then he sang his first time through, and it was like the voice of an angel. It was beautiful.”

While that really is Rooker singing, and Steven Yeun providing his beloved character’s voice in “Happy Glenndings,” and Melissa McBride hilariously deadpanning in scenes that shout out to Carol’s “look at the flowers” moment and Rick’s role in the loss of Sophia, one actor was MIA for Look Who’s Talking. But the Robot Chicken crew wrangled a suitable stand-in.

“When we were going out to the actors from the show, the agent for the actor who played Gareth [Andrew J. West] from Terminus said he doesn’t sing,” Sheppard says. “So Seth put a call into Daniel Radcliffe…”

“As one does…” Meyer jokes.

“Yes, like you would do,” Sheppard continues, “and basically we had Daniel Radcliffe singing the Terminus song.”

One happy coincidence for the Robot Chicken special: The timing worked out so it will premiere before the 100th episode of TWD, which they say allowed them to also include the Talking Dead sketch they’d planned. It’s another clever tribute, complete with voicework by Chris Hardwick, Kirkman, and TWD showrunner Scott Gimple.

“Rob came in at the beginning, and he kind of gave us a lot of guidance at the start of it, and then Scott was in the office, I would say, pretty much half days the entire time,” says Senreich of Kirkman and Gimple’s enthusiasm for collaborating on the project. “They rolled up their sleeves, and our goal was just to make them laugh as much as we could. And both Rob and Gimple picked out their outfits for Talking Dead. They were very specific in what they wanted to wear.”

“I’ve known Chris Hardwick since we were teenagers, so it’s been really fun watching everybody go on their own success path,” Green says. “And then it’s kind of incredible whenever we’re able to find ways to work together, you know?”

Does that make it at all awkward when pitching a spoof of a story or character your friend wrote?

“No, usually there’s not a lot of ego about it, and everyone is willing to look at an alternate interpretation of a moment or a scene or an emotion,” says Green, who adds that no one involved with The Walking Dead, including AMC, set any parameters for the special, other than asking that they include material from the whole span of the series.

“We know each other better, so we’re probably more willing to take risks than if we didn’t all know each other.”

“Everybody came in game for fun,” Sheppard says. “They were ready to roll and let loose. I think for a lot of the actors, both the ones that are still on the show and the ones who’ve been killed off, it was a fun stress relief to just let it all go and be weird with it.”

The Robot Chicken Walking Dead Special: Look Who’s Walking premieres Oct. 8 at midnight on Adult Swim. The Walking Dead Season 8 premieres Oct. 22 at 9 p.m. on AMC. Robot Chicken Season 9 will premiere in the winter on Adult Swim.

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