Earlier this week, DC Comics made it official that "Dark Knight III: The Master Race" will get a little bit longer, as the miniseries -- originally scheduled to run for eight issues -- has been expanded to nine. This means the series -- the third in Frank Miller's future Batman saga, which started in 1986 with the seminal "Dark Knight Returns" -- will stretch out until a scheduled conclusion in spring 2017, after starting in November 2015.

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A big story -- featuring Batman, Superman, Wonder Woman, Carrie Kelley and Lara against the now full-size inhabitants of Kandor -- has now gotten even bigger, especially when factoring in the "Dark Knight Universe Presents" one-shots that are bound into each single issue of the series. The next issue, "Dark Knight III: The Master Race" #6, is slated for release on Oct. 19 and will include a "World's Finest" minicomic, illustrated by Miller and Klaus Janson, starring Carrie Kelley, Lara and Wonder Woman.

CBR News spoke with "Dark Knight III" co-writers Miller & Brian Azzarello about the decision to expand the story, the "dream come true" that is the "Dark Knight Universe" minicomics and the reaction from series artists Andy Kubert and Janson upon hearing the series will get a ninth issue. Additionally, CBR has the exclusive first look at interior pages from the "World's Finest" minicomic appearing in issue #6.

CBR News: Frank, Brian, "Dark Knight III" started out as eight issues -- that's not a small story already, especially given longer than average issues that include the "Dark Knight Universe Presents" minicomics. When did it become apparent you needed another issue to properly tell this story?

Frank Miller: Playing with these characters, they're very big characters, it's a very big universe. There's always a desire to expand it. In this case, there was no reason not to. The material was just too good to stop it so quickly. Also, it offered an opportunity to do something generational -- there could be a passing of the mantle of these older characters onto their heirs, essentially. The opportunity, in the case of both Batman and Superman, was to do something fresh; which is, have both these heirs be female.

Was the story originally conceived with a specific length in mind, or just whatever room you needed?

Brian Azzarello: We had a story; we had a beginning, a middle and an end. Once we started getting the artwork in, it's like, "Oh, god, we should open this up even more." When we went to DC, I think it was in the spring, and said, "We want to make it longer," I think Dan [DiDio] was like, "What, only nine issues?" They wouldn't mind if we kept going.

So Andy Kubert and Klaus Janson were definitely game for more?

Azzarello: Oh yeah. When we mentioned it to Andy, he jumped at it right away. "Yes, I would love to. Let's go one more." What happens in issues #8 and #9 would originally have been happening in just #8, and it would have been kind of tight. I think once you read the two issues, you'll see why.

Miller: When I did the first "Dark Knight" series, I had to stay in the format and the length that was prescribed for me. It became agonizing to contain an ever-expanding story in a rigid format. This time, things are looser, so it can have the room it deserves.

Also, people's attention spans are different now -- you've gotten five issues out, and now the story will stretch out into spring 2017. Is there any concern about a loss of momentum? Or will it not matter once it's all out in one form?

Azzarello: I don't have any concerns about it, at all. We're playing the long game here. At this point, if people are in for five, they're going to go in for four more.

Let's talk the "Dark Knight Universe Presents" one-shots. How much of the fun of the experience has that been, showcasing different characters and broadening out the world -- and the story itself?

Miller: For me, they're a dream come true, because they're just an opportunity to jump in and play around with characters who might not have gotten their own books, and they aren't explored that much in the main stories. They're also just plain fun, to have a little comic within the larger comic. Everything about them is adorable.

Azzarello: Yeah, except the original idea, I didn't like it. [Laughs] It meant more work for me.

What changed from the original idea?

Azzarello: Frank and I had done the whole story, we had this big, sweeping epic. Andy was going to do the story. Then we were breaking out some other stuff, because other artists wanted to work on it. "OK, what can we do here?" We were sitting around, and Dan was there, and Frank said, "Why don't we do mini-comics?" Oh no. Oh no. [Laughs] We had to go back and reconfigure the story. When I say it's extra work, I'm just busting balls, because it has been really rewarding.

It's an extra 12 pages that we're doing -- Green Lantern's not going to have that. We don't have the room for him to have it in the main story. So we put it in here, and it can really breathe. Or Carrie, or Lara for that matter. It's been fun focusing on them.

That's interesting, because originally it appeared it would mostly be other artists on the minicomics -- we've seen Eduardo Risso and John Romita Jr. -- but in recent chapters the art has been all you, Frank. Did that plan change? Have you taken them over?

Miller: Nobody else wants to work with Brian. [Laughs]

Azzarello: That's true. [Laughs]

Miller: Nobody likes him!

Azzarello: Thank god Frank had some time on his hands, otherwise I'd be drawing these myself.

Miller: Brian's been hanging out in front of my place a lot and he's looking very skinny so I figured I'd do some work.

Not sure how much either of you have been monitoring it, but to any extent you have, what's your your take on the reaction to the series from the public?

Azzarello: They seem to like it, right? It seems like every time we go to a convention we're singing a bunch of them. People's reactions have been really good.

Miller: You just can't kill these characters. The fans are devoted to these characters, and they love to see a fresh take on them.

Frank, what has this experience been like for you personally? It's been a while since you had worked with these characters -- to come back to them after a few years and see the work received by fans, how gratifying has the experience overall been?

Miller: It's an absolute ball. For me, it's also a lot of fun to come back and visit the old friends. Particularly, I get the most pleasure out of Carrie and Lara, and having the whole notion of the mantle being passed from these iconic superheroes onto heirs that are female. I think that idea is fresh and fun.

Frank, you've talked about wanting to do a fourth Dark Knight story after this one -- does the extra issue affect those plans at all? Is it still a totally separate thing?

Miller: I still have a story I'd love to do. The possibility has been opened up tremendously. There are always more stories to be told about these characters, but now I've definitely gotten an idea of what I'd want to do with it.

"Dark Knight III: The Master Race" #6, the next issue in the series, is scheduled for release on Oct. 19.