"Frank Miller, in my opinion, and Alan Moore, were punk rock," says comic book writer Paul Jenkins. "They were the absolute change."

In this exclusive mini-documentary, comic industry insiders discuss how Frank Miller's approach to comic books - his grittier world-building, his cynicism, and how he made his heroes face real consequences - changed the medium, especially with his work on Daredevil and Batman. "There was a very significant shift between the very good heroes and the very evil villains and the clean line defining them," comic artist David Finch says. "Frank Miller's The Dark Knight was maybe the most influential book that kind of blurred those lines a little bit."

Adds Charles Brownstein, executive director of the Comic Book Legal Defense Fund: "All of a sudden, you have a whole flurry of books that adults could read that could speak to the nuances and sophisticated problems that adults have. ... [Comics] were illegitimate in the 20th century. In the 21st century, they have become legitimate."

Go inside the conversation of how Frank Miller's work changed the comic book medium in this exclusive min-documentary.

Watch the latest episode now on amc.com and AMC apps for mobile and devices. 

Robert Kirkman's Secret History of Comics airs Mondays 10/9c.  To get more exclusive extras, sign up for the Robert Kirkman's Secret History of Comics Insiders Club.