As the mystery of the entity within Jesse Custer continues to unfurl on AMC's "Preacher," fans at Comic-Con International in San Diego got an early (and unorthodox) preview of the next episode, as the cast performed a live reading of this Sunday's episode. On stage were co-creator (with Steve Dillon) of "Preacher" and executive producer Garth Ennis, executive producers Seth Rogen and Evan Goldberg, and actors Dominic Cooper, Ruth Negga, Joseph Gilgun, Ian Colletti and Graham McTavish. They were joined by Kevin Smith, Jason Mantzoukas, and Danielle Panabaker to fill out the live read.

The panel begins with Rogen introducing the cast and offering a "previously on," before launching into the live read. Still images appear occasionally on the screen overhead to illustrate the scene. Because of the nature of this presentation, the highlights that emerged were less about the episode than the actors on stage and the audience reaction.

There are a few decapitations early in the episodes, which, because of the abrupt presentation of Rogen's script reading, elicit some giggles from the audience and some actors.

"Root continues to eye-fuck him in the rearview" got a few laughs, as well.

Image of a still-burned Cassidy elicits groans, but the look on his face is hilariously wicked.

After a line where Cassidy threatens Jesse rather mellowly, Rogen continues from the script, "contrary to the performance, it's the angriest we've ever seen him."

"You said I could do me own thing!" Gilgun said. "I have to piss so bad!"

After the reading concluded, Smith took over as moderator from Rogan. "You all are doing the lord's work, man!" he said the cast and crew.

"Everyone who's read the comic, or the trade paperbacks, said somebody's got to make this a movie or a TV show," Smith said. He was previously involved in trying to bring "Preacher" to screen, but, he said, "they put my name on it, and nothing fuckin' happened, man!" Instead, it was "two kids from Canada" who realized the dream.

Goldberg said that the original idea was to do an issue-by-issue adaptation, but Ennis suggested this would be a mistake. "We started to realize it just didn't time out," Rogen said, meaning that there would not be enough material for "the fifteen seasons of 'Preacher' we want to do."

"Once we realized we could start changing things, we started looking at all the things we could change," he continued, noting changes to Tulip's character and Jesse's father.

"I realized early on that they were going to have to mess with the comic and I was ok with it," Ennis said. "I maintain that I only confirmed the conclusion Evan and Seth had already come to, that there was only going to be a season and a half worth of material."

"It would have been an amazing season and a half, though," Rogen said.

Rogen said that they "wanted to give the characters, until they enter the main story, their own visual aesthetic," such as the case with the Saint.

"It's like that thing where you start watching a show and you wonder if you're actually watching the wrong show -- that's something we actually strive for," Rogen said.

"You have this wealth of information in the comic book," Cooper said of getting into his character, but he also liked that the show delves more into Jesse's history.

"He's much more dislikable than I thought ... it's very clear to me why this person can contain the entity," he said of Jesse Custer.

Negga said she "kind of lobbied for the part" of Tulip. "I find her quite exciting. I very much enjoy a woman who can be dark and nuanced but also quite funny."

Rogen said that "this is less improv than anything we've ever done, which is why I think it looks better than anything we've ever done."

Asked how he got into acting, Gilgun said he got "into some shit with the police" in his youth and was sent to acting school as a punishment. His father repeatedly thought, "you want to be a fucking prat, you want to be a fucking clown..." then Gilgun noticed the admonition on the back of the panelists' name placards not to swear. "Don't watch 'Preacher' if you're offended by fucking swear words," he said.

McTavish said he was "a huge fan of the books" and read them as they came out. "When I heard of they were doing this, I desperately wanted to be a part." McTavish said he felt an enormous responsibility to the role when he suited up for the first time.

Colletti, though, was not familiar with the comics. He researched, though, and said for his audition tape he "had spit and drool all over myself."

"I thought you were going to tell us you used your asshole," Gilgun said.

Colletti said the Arseface/Eugene makeup takes two and a half hours to apply, and he can't eat or sneeze once it's on.

Rogen said he cold-emailed Sam Mendes in 2008, who was then attached as director to "Preacher." "You've never met me but I am writing to tell you I would give anything to play the role of Aresface," Rogen wrote. Mendes replied saying he'd let him know if there was a chance to audition, but that never came to pass.

A fan asked how each panelist would use the Genesis entity on the crowd and what they would say. Only Gilgun answered. "Everybody start shagging." After a bit of cross-banter, he added, "I come amongst you like a mist of syphilis and chlamydia."

Asked how Gilgun and Cooper got along, Gilgun said their friendship is a lot like Jesse and Cassidy's and, after a lot of banter, added, "and we kiss a lot behind Ruth's back."

"He's not a gentle lover," Gilgun added. "Quite rough."

As to how Tulip can be such a strong character and still give Cassidy drugs and hook up with him, Gilgun swore a bit about her self-destructiveness. Negga added that she "quite liked that beat" as it showed her returning to things she knows in the midst of conflict. Rogen agreed, saying that a strong character can still be flawed.

Asked about favorite scenes, Ennis cited a few but added, "I love that they've solved all of the storytelling problems from the comic."

"They've found plausible reasons for things I just chucked in," he said. "Things that work in comics don't necessarily work when you see them acted out on film. These guys have solved all those problems and I applaud them."

"People considered 'Preacher' unmakeable for at least a decade," Rogen said in response to a question about the show's potential influence on other comics properties. "Hopefully this will show people that other unmakeable comics can be made."

Asked about his reaction to fans nitpicking the show, Ennis said "the most important thing is that it works." "The thing you have to hold in your head is that certain things had to go to make the thing work."

Rogen said he's actually pleased with the response. "We made the fucking Green Hornet, dude. This has been a dream as to how people have embraced it."

Goldberg said "Walking Dead" paved the way for 'Preacher" at AMC, and "taught them how to deal with this sort of big world." Rogen joked that it allowed them to say, "that was a comic, they did it," but more straightforwardly added that the AMC relationship is great.

"Some of the heads of AMC are great 'Preacher' fans," Goldberg said, "and they want it to be rad, too."