Here's what it's like to be zombie extra on "The Walking Dead"

Greg Crews knew it was going to be a big deal when he received the phone call. Looking back on it now, though, he didn't realize being an extra would lead to eventually getting an agent and a long list of additional acting opportunities. Plus, he will remain forever cool in the eyes of his young son and every "The Walking Dead" fan out there.

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Crews portrayed "Greg," better known as "the snoring guy" in season four of the AMC drama, "The Walking Dead." He appeared in scenes filmed inside prison cell block "D," but he was featured in episode two, "Infected." The show's co-executive producer Greg Nicotero, who also serves as one of its directors, chose Crews for the role.

"When ECA (Extras Casting Atlanta) called, they told me Greg Nicotero had personally picked me for this," Crews said. "They said pretty much, 'you're going to be killed in your sleep by a walker and then you're going to kill a bunch of other people.' "

The tiny part they failed to mention is that Crews would get his guts ripped out, turn into a walker and promptly be killed by none other than crossbow-slinging Daryl Dixon (Norman Reedus). The scene was shot in reverse, starting with a walker killing him in his sleep inside the prison. He was in makeup for hours.

"My first piece of advice is to shave," Crews said. "Chest hair, wherever they will be doing makeup. They use latex, which is glued onto you. It takes a while to put on and it's itchy. They actually shade each piece and stay right with you throughout the filming, checking to make sure all the special effects and makeup stay in place."

Crews admitted he was star-struck before he ever walked onto the set. One of the show's stars is British actor Andrew Lincoln, who plays Rick Grimes. Lincoln has perfected a distinct laid-back Southern twang for his character's voice. Crews said when Lincoln came up speaking in his normal voice with a British accent, he couldn't believe what was happening and that he was a part of it. His scene included working with actor, Vincent Martella, whose credits include "Everybody Hates Chris" and was the voice of Phineas Flynn in the Disney Channel's original animated show "Phineas and Ferb." But the star treatment didn't stop there.

Nicotero personally worked with Crews to perfect his zombie walk. According to Crews, Nicotero told him to relax, and think of it as being two or three o'clock in the morning; you're leaving a bar where you've been drinking for several days.

"That's the way he told it to me and that's the way he told it to everybody that's been through zombie school," said Crews.

A majority of people cast as walkers are required to attend "zombie school," which is taught by Nicotero.

"(Nicotero) is very precise in what he wants," Crews said. "You can tell how long the show's been running by the length of his hair. I don't think he's had it cut since the pilot."