Warner Bros. Animation has produced another animated anthology of short films based on iconic DC Comics characters with this year's DC Showcase: Constantine - The House of Mystery. The anthology is headlined by a John Constantine story, featuring Matt Ryan returning to his fan-favorite role in an extended epilogue starring the Hellblazer after the cataclysmic events of Justice League Dark: Apokolips War. The anthology includes three other animated shorts, from a World War II story starring The Losers to tales based on Kamandi and Blue Beetle, echoing their respective classic visual styles.

In an exclusive interview with CBR, producer Rick Morales shared the visual inspirations behind this iteration of DC Showcase. He explained how the format lets the filmmakers experiment with adapting classic DC characters and revealed some of his favorite elements behind the anthology project.

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Scene from Constantine and the House of Mystery.

CBR: With this set of DC Showcase shorts, a lot of it is a love letter to Jack Kirby, like the Hanna-Barbera Kirby cartoons we never got. How was it putting this anthology together?

Rick Morales: It was a lot of fun! There was a point when we were working on it where I was like, "I can't believe they're letting me do this!" [laughs] I'm making a '60s-style Blue Beetle show, and we've got all these intentional mistakes in it and doing it as a complete love letter to this stuff. It was a joy, and this is one of those things you look back on in your career and go, "That was a great time!" because we got to touch on all these things that we love. I tried to honor them as best as I could and directly, as much as possible, [let] these comics come to life on screen. That was my goal.

Was it always in the DNA to have at least one of these shorts be a continuation of Justice League Dark: Apokolips War?

I get a call saying we're going to do some more DC shorts and [asking] if I was interested in overseeing it. I said yeah, and then we had a discussion about what we were going to do. [Producer Jim Krieg] already had some thoughts on this, and the Constantine Apokolips War epilogue was already something he had in mind. That was going to be the linchpin of this, the main feature. That was already set in stone, with the House of Mystery, so it was figuring out what that was going to be.

With the other characters, it was about who we hadn't done yet and who we were the most excited about. Kamandi is something I think that a lot of people at Warner Bros. Animation have had an interest in doing for a long time, and there were even some attempts made around it. This presented an opportunity to do it as an 11 or 12-minute short, so we could be as faithful as we possibly could to the look and feel of the Kirby comics. With that set, what I wanted to do with this was make a direct adaptation, at least in terms of look, feel, and visual style of the visual comics that we love.

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dc showcase kamandi

A lot of the backgrounds in the Kamandi short feel like they're straight from the covers and splash pages of Kirby's Kamandi: The Last Boy on Earth.

Yeah, they are -- not that we could take those pages directly and reproduce them and color them. The Statue of Liberty shot, which is so iconic, has to be there. The discussion with the background designers was literally, "This is what it looks like, so let's try to match this as closely as possible." Even within those storyboards, to the credit of [director] Matt Peters, he took images from the comic panels as closely as he could and just translated them. We were able to go to those particular issues of the comics, look at the backgrounds, extrapolate the information, break down the layers for the multi-plane, and then we're off to the races. Obviously, we had to create a bunch of new backgrounds, but it was all based heavily on Jack Kirby references.

The Losers short, written by Tim Sheridan, is exemplary of the whole anthology: a historical war story that quickly veers into science fiction. How is taking all these seemingly disparate characters and figuring out who would be working with them for this project?

After we nailed down what characters we were going to use and basic concepts of what that story might be, Jim Krieg goes out to various writers. With Tim Sheridan, we felt like [The Losers] was probably the one for him to do. It just sort of became that: which writers do we have, where do we think their strengths lie, and which are the characters they'd have the most fun with. That's how we approach bringing in these writers.

As far as the disparate nature of some of these stories, I feel like, with the shorts, you have an opportunity to experiment a little bit. You're not beholden to make a 70-80 minute film. You've got maybe an 11-minute short to condense all your ideas down. Because of that, there are restrictions on the types of story you can tell, but there's also a lot of freedom in how you can approach it because you don't have to worry about it being a feature-length film. Can something with this art style carry a 70-minute thing that looks like the comic book?

In Kamandi's case, the colors were all trying to match the comics and the color palette of the time. That might not work for a 90-minute thing, but here, it certainly does. It does open up, stylistically, some freedom that you can take.

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dc showcase blue beetle

One of the highlights in this anthology is the Blue Beetle short, channeling 1960s superhero cartoons with Charlton Comics characters. How was it working on that?

It was such a joy to work on. It really was just pure fun. When we came up with that concept, on the way that we were going to go, it was very much knowing exactly how it needed to look and exactly the filmmaking [style] that needed to go into it. Sometimes you're making something and finding that stuff, but with that one, in particular, it was like, boom. This is what it's going to look like. We leaned into that as much as we could. We went back and watched Super Friends and Spider-Man, looking at the errors and types of limited animation that they had, given their schedules, and trying to emulate that, not to deride or make fun of but show love for those things.

I'm young enough where I didn't see those cartoons when they first came out. I saw them in reruns, but a lot of people on the crew are younger than I am and don't know that stuff well. In bringing these artists along, it was pointing out what shots were too dynamic and where the animation is too expressive, having to pull it back and cut in a certain way. That part of it was really fun, to get to run wild making choices you wouldn't normally make.

I know it's like picking your favorite kid, but as you and voice director Wes Gleason were putting this cast together, who really blew you away with their performance?

That's difficult to answer when you have someone like Ming-Na Wen coming in to play a role. To me, Lou Diamond Phillips as the Spectre, that was just a home run. With Wes, we had discussions about who would be good for this role, and he threw out Lou, who just hadn't occurred to me at all. When [Wes] said it, I was like, "Oh crap, that's absolutely perfect!" I remember recording that remotely, and he was such a nice guy, so down to do this. That voice, as soon as it came out of him, it was the Spectre. I could feel it. That was the one that really hit for me.

Produced by Rick Morales and Jim Krieg, DC Showcase: Constantine - The House of Mystery will be available May 3 on Blu-ray and digital HD.