EW: New Details Revealed In Behind-The-Scenes picha 

’s season 4 premiere on April 15, new showrunners Andrew Chambliss and Ian Goldberg share exclusive snapshots from the set in Texas.

“This was Lennie’s first day on set. He only had four days in between

,” says Goldberg (far right, with actor Lennie James and Chambliss).”We have Morgan going places emotionally that he didn’t on

“We were excited to take advantage of our new location and put the characters in situations that were very specific to Texas,” Goldberg says of coating actress Jenna Elfman (left, with stunt coordinator James Armstrong) in oil.

“Her weapon is a bit of a surprise,” Chambliss says of what Maggie Grace (with stunt coordinator Jack Tamplin) is holding. “I think people will be excited to see it in action.”

“Maggie plays Althea, one of our new characters on the show. Al has a really interesting backstory; she’s uniquely equipped for the appocolypse and has a pretty strong puppose that drives her,” says Goldberg (with Grace). Adds Chambliss: “I knew Maggie personally before working on this show, and what’s funny is that my wife suggested we look at Maggie for this role and that same day our casting team sent over her audition. We had been looking for the right Al for a long time, and we watched Maggie’s read and the moment she walked on screen, she had the character down.”

“During location scouting, a SWAT team in Round Rock [Texas] let us ride in their van, and they had a hula girl on the dashboard; we nod to that in ours,” Chambliss says of the vehicle Althea drives.

Dan Liu (front with writer Shintaro Shimosawa and Grace), who serves as an editor and director on

’s third episode this season. “The SWAT van is very much a character this season, particularly in this episode,” explains Goldberg. “We start to understand its importance and why it means so much to Al.”

“Dan was a great partner early in the season in getting us going,” Goldberg says of Liu (with actor Frank Dillane). “Here, he’s directing a pivotal scene for Nick, and we’re very excited about the way it turned out.”

“We want to give the fans moments this season with walkers that they’ve never seen before,” says Goldberg. “And between

they’ve already done a lot, so that’s been a big challenge.” Adds Chambliss: “We keep asking ourselves, ‘What’s this walker’s backstory?’ That’s given us some great inspirations.”

“We came into this season new to working with everyone, and the cast could not have been more welcoming,” says Goldberg. As for this shot in particular? “We find our characters in a baseball stadium this season,” he says of the photo (from left: Dillane, Colman Domingo, and Alycia Debnam-Carey). “We can’t really tell you much more ….”

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