Returning to Comic-Con International in San Diego after a nearly ten year absence, director Robert Rodriguez and "Sin City" creator Frank Miller were proud to present a clip from the upcoming sequel, "A Dame to Kill For" for attendees. Stars Rosario Dawson, Josh Brolin and Jessica Alba joined the co-directors to discuss the evolution of the film, working on green screen sets and, perhaps their greatest challenge, getting Miller to smile.

As the hour began, Rodriguez remembered what it was like before the first "Sin City" film was realized, and the conditions under which comic book adaptations typically came to the big screen. "People would think you had to adapt comics into movies; that they were separate forms," he said. "I saw that Frank was doing the most groundbreaking visual storytelling in any medium, and I couldn't understand why you couldn't take that [directly] to the screen." Almost ten years later, industry approaches have changed thanks to the first film offering "a new way to look at technology and graphic novels."

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"The comic book movies that have been coming out have been getting better because they're closer to the source material," added Miller. "It's one thing to sit at a drawing board and then test [a concept] in a relatively small market, then throw it into a boardroom with a bunch of people that think its crap." Citing his own experience writing screenplays for Hollywood, Miller likened a script to "a fire hydrant with the dogs ready to piss on it."

In fact, it was Miller's frustrating sojourn into Hollywood in the late 1980s that led to the creation of "Sin City," though his desire to tell crime stories goes back to his earliest days in comic books. "At the time I started, they only published stories about men in tights," he said. Finding the balance between crime and superheroes led to his celebrated runs on "Daredevil" and "Batman." Then came screenplays for movies like "Robocop 2," but finding that job had "too many bosses," he moved on, creating "the comic book that could not be adapted to the movies. It was 'Sin City.'"

"Then, this crazy Texan showed up and showed me how to [adapt] it."

Following a screening of a few minutes from "Another Saturday Night," which will open the sequel, the actors joined Miller and Rodriguez on stage. Alba returns as Nancy Callahan, though she warned that sweet little Nancy has gone through a tremendous change. "It's an original story that Frank and Robert developed," she explained. "I got to participate in that as well, over the last decade. I think people will be surprised to see her turn into a warrior." She added that getting to work with such material made her feel like "the luckiest girl in Hollywood."

"I wanted to play Nancy, but it didn't work out," quipped Brolin.

Brolin takes over as Dwight, the character played by Clive Owen in the first film -- though, by the virtue of the story taking place before any of those in the original adaptation, he is actually playing a younger version of the character. Asked what helped him connect to the material, the actor replied, "You don't know it connects with you until you're a part of it." He citied his twenty-one year friendship with Rodriguez as part of the reason he chose to come onboard, adding, "you're dealing with two total iconoclasts" as a final reason to sign up.

"To be involved with that," he continued. "You have to dive into what Frank has created."

Part of the diving in includes working with Miller's anachronistic dialogue. "You can't naturalize it," said Brolin. According to the actor, modern acting is very much about naturalistic dialogue, but attempting to do that with Miller would mean the characters would lose too much of their power. Instead, the actor had to become part of Miller's world.

Dawson agreed that the energy would get lost if they changed Miller's dialogue.

While working with Miller's material could be difficult, having him on set was a special delight for the cast. "To have Frank there, it was great to see how giddy he would get [when we got things right], " the actress explained.

"We'd want to get Frank's signoff on a scene, and we'd know we got it if he had a big grin on his face," Rodriguez continued. "He dreamt it up so long ago and never expected to see it performed. That was always the goal: Make Frank happy."

This was part of the reason Rodriguez fought to have the first film branded as "Frank Miller's Sin City." He felt Miller was so central to everything that he needed to be in the title "so that his name would be there when you look it up." Rodriguez saw himself more as "a facilitator" of the directorial choices Miller already made in the pages of the comics. "The Directors Guild didn't get it when I tried to explain that he was already a director," he said. The ensuing battle led to Rodriguez leaving the guild.

Acknowledging the long period between the two films, Rodriguez said, "It couldn't have happened before now. We wouldn't have the cast." The director believed that the group, which also includes Ray Liotta and Joseph Gordon-Levitt, were aided by the lag time as the rest of the industry got used to green screen sets and digital cameras.

"Back then, people didn't know about green screen," he said. "Now, people know what they're doing. The performances are ten times better."

The magic of the green screen led to the solution of one problem for Brolin, who was excited to work with Mickey Rourke for the first time in his career. However, the actor's tight schedule ultimately precluded them from working together. Instead, Brolin connected with Rourke via video of his performances. Rodriguez got the idea from the powerful chemistry between William Shatner and Ricardo Montalban in "Star Trek II: The Wrath of Khan," which came from the two never actually meeting, and Shatner reacting to footage of Montalban from a month earlier in the production.

"From that moment on, I only knew about movies by myself," said Brolin. "You want to connect with the person you're acting with [generally], but Robert just blew that to smithereens."

Ultimately, Brolin felt he just had to put his faith in the director and in Miller's vision of the story. While he might be acting on a small, green set, Rodriguez and Miller already see him on a cliff with an amazing cityscape behind him. "It was just a big blackout for me," he added. "But when you watch the movie, you get to experience it as thought you've never read the script."

Miller noted that the entire cast felt more comfortable diving into the world of "Sin City" this time around, saying "the whole world got used to the idea of 'Sin City.'" Returning cast members Dawson and Alba came to set in character and ready to work. "When Jessica showed up, she barely said hello to me because she was ready to do a graveyard scene," Miller recalled. She was so focused on the work, he though, " I haven't seen her in eight years -- how did I piss her off?"

Explaining herself, Alba said, "I connected with the dark side of Nancy and it was hard to detach from that until the movie was over. The whole time I was in Austin [TX], I connected to that spirit."

Rodriguez added, "Nothing would break it."

Alba also suggested her relative youth on the first film left her feeling intimidated by Miller's world. "The second time, I felt comfortable in my own skin and I wanted to kick ass."

"It's breathtaking what she becomes," Rodriguez said.

Miller also sketched on set. In one instance, Alba contorted her body to match the exact pose of Nancy in Miller's drawing. When he asked why she did that, she simply responded, "That's how you drew [it]."

The production speed meant Miller's sketches could be realized and shot more quickly than he could finish the pictures, something Rodriquez said was due to the advances in technology over the last ten years. Pulling out his smartphone, he said, "We didn't have these." He initially planned to let someone else score the film, but found he could carve out time by humming possible score into his phone's voice note app. "I'd work it out [further] on my keyboard, and that was the score. I'd bring it to set the next day and Jessica could act to it."

Miller joked, "So you were phoning in the score?"

"Creation doesn't have to be a long process," Rodriguez continued, saying he liked to keep shooting at a brisk pace. If a lull did occur, Miller was there to set him right, shouting, "Shoot, dammit! Shoot!"

When the floor opened for Q&A, a fan wondered if Miller felt he got lucky with the adaptations of "Sin City" and "300." Miller said because both Rodriguez and "300" director Zack Snyder committed to bringing his visual sense to the screen, "It was never an issue. Now, I'd be a real prick."

Asked if the two might pursue another collaboration, Miller answered, "Robert and I are already talking about 'Sin City 3,' so you better show up for number two or they won't pay for it."

Miller also said another "Sin City" graphic novel was inevitable. "I've got a stack of stories I want to do. I would say yes, but what year, I'm not sure."

Asked if his Martha Washington character might make her way to the screen someday, he replied, "It will happen -- but it's gotta be done my way."

The final question revolved around the necessity in recasting the Manute character following the unexpected death of Michael Clarke Duncan. Rodriguez fielded the question, saying, "The common thread is that everyone wants to be true to the material. Dennis Haysbert came in, and since it's a prequel, it works really well." He called the actor's performance "stunning. It's going to make you want more. It takes an artist and a gentleman to do that. It sometimes takes many people to play one part."

Following a revised trailer for the film, Rodriguez closed the session by promising, "Next time: part three."

"It won't take nine years this time," added Miller.

"Sin City: A Dame to Kill For" opens August 24.