The DC Animated Universe is about to gain a new Green Lantern in the upcoming animated feature film Green Lantern: Beware My Power. Directed by Jeff Wamester, the movie brings together veteran animation screenwriters John Semper and Ernie Altbacker to craft the cinematic adventures of John Stewart as he inherits a Green Lantern Power Ring and finds himself in a cosmic confrontation for the fate of the cosmos. For the reunited Semper and Altbacker, the opportunity to reintroduce a new version of Green Lantern to modern audiences was too good to pass up.

In the first part of an exclusive interview with CBR, Semper and Altbacker shared the themes behind Green Lantern: Beware My Power. The pair also revealed one surprising cinematic influence on the story and reflected on their career together.

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CBR: Gentlemen, what are the origins of Green Lantern: Beware My Power?

Ernie Altbacker: The origins of this I would lay at the feet of [producer] Jim Krieg, who called me up and said, "I've got a great idea doing Green Lantern. We kind of want to do a different story, and it's going to star John Stewart, and you'll be partnering up with John Semper." I went, "That sounds fantastic!" It was an honor for me to work on this with John, especially because John gave me my first job in the industry on Spider-Man: The Animated Series, and I'm sure he gave Jim his first job. Jim had done things before, but I think this was the first real thing. John was kind of a mentor. I had come out of the AFI and thought I could write, and I didn't realize I couldn't write until John started teaching me how to write. This whole circle came around, with Jim in charge of this, and it was a fantastic experience for me.

John Semper: We're old friends, and when I found out that I'd be doing this project with Ernie, it was great. I knew we were going to have fun. The first inkling I had was when I had lunch with Jim, and he said, "I've got a thing I want to do, and I'll get back to you." That was like four years ago! [laughs] About a year later, we had breakfast, and he said, "I want you to look over the Neal Adams and Denny O'Neil comics with Green Lantern and Green Arrow, and I'll get back to you." About a year passed, and we finally started to talk about a real project. That's kind of how it went for me.

When we first see John Stewart, he's at the lowest we've ever seen him before, with lots of unresolved trauma in his life. Why did you want to start him so low at the beginning of the story?

Altbacker: We wanted him to kind of start from a nadir point, and we wanted it to have Heart of Darkness/Apocalypse Now in the storytelling, where we're going on this mission. It's kind of where we see Captain Willard at the start of Apocalypse Now, drunk in his hotel room, and then we put this guy on a mission. We couldn't do this in the Swinging '60s, but we started it out that way.

Semper: The whole theme behind Apocalypse Now is that, in order to escape the jungle, you have to go back into it. When Apocalypse Now begins, he's out and not in battle at that particular moment, but he's sort of out of it. He knows he has to get back into it in order to escape the trauma. We basically start with a character who is suffering from post-traumatic stress disorder and has to find a way to deal with that within himself. It's very much the story of one man finding peace with himself and understanding how he can continue to live the rest of his life. That really is the core of the story.

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John's trial by fire takes him in the middle of a conflict between Rann and Thanagar. What was it about having that being the setting for this cosmic odyssey?

Altbacker: That all dovetailed nicely with Apocalypse Now traveling up the river juxtaposition in that we were going to go to space and through this war zone of the Rann-Thanagarian War.

Semper: That was our battleground and the dark tunnel that our character has to basically go through in order to find the light at the end. That was something that Jim pretty much gave us to work with, and it was a perfect situation to exploit for this kind of story.

While John was introduced during Green Lantern/Green Arrow by Denny O'Neil and Neal Adams, we haven't really seen Oliver Queen and John pair up all that much in the comics. What was it about bringing this iteration of the hard-traveling heroes together?

Altbacker: We have our damaged John go through the fiery crucible to come out on the other side of it, and since there was this Denny O'Neil and Neal Adams pair-up, it was like, why not have the Green Arrow be his partner? The great thing about Ollie is he is also a breath of comic relief. He's far lighter in tone than John Stewart at the beginning. If we had paired him up with somebody a little more grim than he is then the tone of the movie becomes a little too dark. Ollie serves that purpose, and he's a great character.

Semper: I think it's iconic to have the Green Lantern and the Green Arrow partnered up. It's just one of those iconic partnerships that you want to see, and that hasn't really, to my knowledge, been brought to life before on the big screen. To have the opportunity to do that for the first time was just exciting, and we try to do as many cool things as possible over the course of these films. [laughs]

Altbacker: John, Jim, and I are big fans of fan service, and we know [the fans] will go nuts and think of the hard-traveling heroes, it should be Ollie.

Semper: Jim handed me the softcover [comic collection] and said, "I want to do something like this!" I had read it when it first came out, and when it first came out, it blew me away. I'll never forget that scene when Green Arrow gets mugged, and he's trying to find a phone booth in New York that would work. The little things that you'll remember, that was something that was indelibly etched into my mind, and I'm old enough to have picked that comic book up when it first came out, so this was something we really had to do.

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Voice and casting director Wes Gleason has brought together a really great cast for this movie, including Aldis Hodge as John Stewart and Jimmi Simpson as Green Arrow. How was it seeing them bring the characters and story to life?

Altbacker: Warner Bros. always has such great casts that they assemble. It always surprises me, the talent that they can pick, and they did wonderfully when I saw the movie. Wes did such a great job again, and Gary [Miereanu] is sometimes involved in that also, I think.

Semper: We're really just passengers on that. You write the script, send it off, and are just delighted when it's done by really competent actors that people are excited about. That's just really a birthday present to us; we are beyond thrilled.

You both have known producers Jim Krieg and Butch Lukic for a long time. How was it working with them on this particular project?

Semper: Easiest project I think I've ever done in my life. It was like a hot knife through butter. My joke is that I'm still waiting for the difficult notes. We met with Jim, and the three of us hashed out the rough story beats. I don't even think we did an outline.

Altbacker: I think [after working with Jim], we pitched Butch, and he was in on it. He tossed some great ideas in, and we did an outline, but it was quick, like a beat outline.

Semper: The funny thing is normally this process is agony, and, by the time you're done with it, you don't want to even see the finished product. [laughs] What's funny to me is that I remember writing the script, but it just went by so effortlessly, and we were all in agreement and enjoyed being in each other's company, which I think is a huge part of this. I don't even really remember, it all just went really quickly.

Altbacker: I think part of that is when you have two writers, and the writers work well together. If you have two, and they're not on the same page, then it's the worst. [laughs] After we got the go-ahead to get to the script, we split it into halves for the first draft and just constantly asked each other questions. I'd say things like, "I'm in the first act putting in this. Can you have Green Arrow do this thing to pay it off?" and he'd say sure or have something to set it up in the first fifteen minutes, and I'd put that in. Writing 50 pages isn't that bad, as opposed to an entire script. It should be half as hard, but it's easier!

When we handed it over to each other, it clicked, and we estimated that we lost half a page. The two halves clicked together almost perfectly, and then we'd pass it back and forth a few times, and it was done. We did get notes on this and a second set of notes, but it was fast, maybe our fastest one. I hadn't done a co-write before. I had been asked to come on after another writer had left to do another project. I would go in with new mandates and do a big rewrite, which is sometimes harder than just doing it yourself.

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Without going into spoilers, were there any cut moments you both had written that you would've liked to have seen in the final film?

Altbacker: I'm cribbing off John here, but when we saw the movie, he said he agreed with nearly all if not all the changes that they made.

Semper: It was cleaner and faster. Every single one of those changes improved the story, and that doesn't happen often. Every one of the changes that they made improved the story, and I thought that every one of the additions they made that we weren't responsible for -- there weren't many, but there were a few things that had been indicated in the script and embellished in the film -- all of them were great, intelligent, and moved the story along even faster and better.

There were a couple of things that I'm not going to go into, changes that would've worked just as well as it was written, a couple conversations that got taken out that maybe I would've liked to have seen. Really, I think they improved it, and, overall, I'm ecstatic about the film. I don't always say this about my work, but I just think this is a real movie. When I saw it, keeping in mind that I knew what was going to happen, it still resonated with me a couple of days later like a good movie should. It looks great.

Altbacker: If I had to say something, the script was probably a little long, and there were some conversations between John and Shayera that had to be trimmed because it had to be made producible. It's still 85 minutes and went over; usually [these animated movies] are 72. The relationship is still there and strong, and it's good.

Now that you've seen the finished film, what are you most excited about getting to share it with the world?

Altbacker: I think we both hope, in some small way, that this project will put John Stewart into the pantheon of DC's greatest heroes where he belongs.

Semper: And where people have been waiting for him to belong. I think one of the reactions that I noticed on social media is that there's a whole generation that grew up with John Stewart as their Green Lantern, and they've been waiting for him to appear on-screen. It's kind of like it's long overdue. For those generations of DC animated fans, this is going to be the greatest gift that they've ever received.

I'm in my 40th year as the first Black animation writer, certainly in TV history, the first Black animation showrunner. I've had a good career and done some really cool things, and it is so wonderful in this stage of my career and life as a Black writer to be able to handle this iconic character, DC's first real Black superhero of note, and to be able to reintroduce him on-screen. I was the producer and head writer of Spider-Man: The Animated Series in the '90s, where I got to introduce Spider-Man to a whole generation and introduce concepts that are still resonating and echoing throughout the Marvel Cinematic Universe. It really is an amazing experience to be able to do this again, to be able to take a character that is iconic, major, and a character of color -- especially in this era -- and reintroduce him on-screen.

I'm thrilled and excited to be handling this character at this stage of my career. This is my 40th year, so this is a really cool experience for me, and I just wanted to thank Jim and Ernie for making it possible to be part of this particular party because it's a great part to be in. These guys started out as my employees, they became my friends. They're incredibly talented, and I taught them well. Look at the career that Jim has now, where he's doing all this amazing stuff. This is my reward for all the stuff that I've done, to see this happen with these two and getting to now be a part of it. I'm a very content guy these days, and to be at my stage of life and be content and excited about the movie, it's nice to be me, and thank them for that.

Altbacker: It's not like it's only Jim and me, but many people got their first credit on Spider-Man and other things that John did, and many people had their careers reinvigorated by him, and I'm certainly thankful for it.

Directed by Jeff Wamester from a screenplay written by John Semper and Ernie Altbacker, Green Lantern: Beware My Power will be available July 26 on digital HD and Blu-ray/4K UHD.