A few moments after concluding the large-scale press conference for "Batman v Superman: Dawn of Justice" on a Warner Bros. studio soundstage, the latest actor to don the cape and cowl -- who also happens to be an old school comic book fanboy -- confided to CBR News exactly why he was able to assume the mantle of the Dark Knight with some degree of assurance.

"The fact that the bat was shaped like the Frank Miller bat, and that we were taking inspiration from that book specifically gave me a lot of confidence," revealed star Ben Affleck. "Because I knew that deep down the story worked. That deep down the tone was good, the story was good. [Screenwriter] Chris Terrio did a brilliant adaptation of it, and I knew that Zack [Snyder, the film's director], whose powers of visual storytelling are really enormous, would be able to do a fine job with it -- Once I found out what they were doing, I said yes right away."

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Growing up in Boston, Affleck was a regular reader of comics, and during the press conference he vividly recalled how in 1986, at age 14, he discovered Miller's landmark take on the enduring superhero, "The Dark Knight Returns." "There's a store on Mount Auburn Street called Millionaire Picnic, which is still open I think, which is wear I bought the Frank Miller book," he said.

"That's where I bought those first comics, and that was the first comic that really took my appreciation of this genre to another level," he said. "It was right when people were kind of innovating that way, when 'Watchmen' came out around the same time. Newer, more adult, sophisticated, complicated ways of looking at this world started to be developed within the comic genre."

Affleck said Miller's story, which nearly singlehandedly redefined how Batman would be written and depicted in both comics and a myriad of multimedia appearances to follow, "was really original and interesting and turned the genre on its head. It's a morally grey sort of story, and changed the way I saw comic books. So I had been familiar with that idea for a long time. When I heard that this was the idea of this movie, I thought, that's brilliant because it's one of the great ideas in comics that hasn't been mined yet for films.

"It took the movie business 20 years to catch up," he added, "to be willing to really mine these stories and this genre for complicated and interesting and resonant, rich stories -- but it has now, obviously."

Thus familiar with the seminal inspiration, Affleck had an easy time wrapping his head around a film built around an epic Batman/Superman conflict. "I was always ready tuned in to what it could be and hoping that was the angle that Zack was taking. He had the little sculpture from that in his office. I thought, 'This guy's definitely on the right track.'"

"For me, there was really enough material in the screenplay that Chris Terrio wrote and with Zack's direction, there was plenty for me to grab on to and use my imagination to try to build this character," the 43-year-old actor said. "It's certainly daunting because of the people who have played this character before, and the great filmmakers -- most recently, obviously, Christian [Bale] and Chris [Nolan] did three brilliant movies, and all the guys who went before them. There's that element of sort of healthy respect you have for the project and for the characters and their history, and you know raises the bar certainly. I felt I was in really good hands with this script and with Zack, so that was where I focused my attention."

"Zack often said that he thought Bruce Wayne was kind of a mask or a character that he put on, as much as Batman was," Affleck said. "He liked the idea that there was this ritual: just putting on the suit and getting ready, the way he looked and the whole thing was like a way of putting on a mask to the world and presenting this alter ego Bruce Wayne person to the world. I thought that was interesting. I liked the idea that both Bruce Wayne and Batman were really sort of fucked up, unhealthy people who were engaging in unhealthy behavior at night as a result of psychological scars from childhood. I thought that duality was something that was really interesting to explore."

An accomplished and acclaimed filmmaker himself -- he shared a Best Original Screenplay Oscar with Matt Damon for 1997's "Goodwill Hunting," and his most recent directorial effort, "Argo," won Best Picture in 2012 -- Affleck also relished in absorbing lessons from watching Synder at work on the colossal production.

"One of the really valuable things about it for me, aside from just the whole experience of playing the part," said Affleck, "was watching a guy who really understands how to make films on this level with the cutting edge technology, combining in-camera stuff with visual effects, and stunts, and practical effects -- all the tools at a director's disposal, and seeing how Zack meticulously constructed them using literally hand-drawn storyboards frame by frame and evolving those into the movie that you saw.

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"I wondered about directing movies like this before, and it was really a very valuable learning experience for me to watch Zack do it and see how he did it, so that I felt like if that day did come, I definitely picked up a lot of valuable information and tricks." He's even open to helming a Batman film himself. "For me as a director, it's about material and the characters, so if I found the right material, I would definitely throw my hat in the ring to direct something on that scale. I'm definitely emboldened now."

He's also become a student of the character himself, developing a deeper understanding of his resonance over nearly eight decades. "With Batman, I think one of the reasons why this character has resonated since the FDR administration with audiences, regardless of the way the country's changed and pop culture has changed, is because you have a guy who on the one hand is powerful and exciting and can do things that we all wish we could do," Affleck explained. "But he's also still a human being and struggling with his own vulnerabilities and fragilities and struggling with his own will. And he accomplishes things by force of will."

"That was fun and exciting to play," the actor said. "I think it tapped in equal measure my adult geek-ness and kid-excitement for this movie. Every day there was something new to geek out about and be excited by -- and be like, 'I can't believe I get to be in this movie.'"

"Batman v Superman: Dawn of Justice" opens March 25 in theaters.