The DC Universe Animated Original Movies line continues to build the Tomorrowverse that began with 2020's Superman: Man of Tomorrow, with its latest film Legion of Super-Heroes. Directed by Jeff Wamester from a screenplay written by Josie Campbell, the animated movie brings Supergirl (Meg Donnelly) to Earth, where she hones her superhero abilities by training with the Legion of Super-Heroes in the 31st century. As Supergirl finds a place among Brainiac 5 (Harry Shum, Jr.) and the rest of the far-future heroes, a sinister threat menaces the Legion from within.

In an exclusive interview with CBR, veteran DC Animation producer Butch Lukic shared the origins of the Legion of Super-Heroes' inclusion in the Tomorrowverse, revealed behind-the-scenes secrets for the animated movie, and teased what fans can expect from Legion of Super-Heroes and the Tomorrowverse's future.

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CBR: You've been quietly assembling this new vision of the DC Universe with a grounded side in Batman: The Long Halloween and cosmic scope in Green Lantern: Beware My Power. What makes the Legion of Super-Heroes the next piece of the puzzle?

Butch Lukic: It was more that we wanted to introduce Supergirl into this universe. We figured out that it was always going to be Supergirl and the Legion of Super-Heroes, so when we got to this point, we got [screenwriter] Josie Campbell in. She started doing research on the Titans stuff and came across this obscure group of villains, and that tied in with stuff we needed to happen with a certain villain.

Originally, we were talking about going with the bigger Legion of Super-Villains, but I didn't want to go down that route. [Josie] pretty much came up with this whole storyline. On our end, it was to build up Supergirl plus have the Legion in it somehow. With both of those requirements, we put everything together. I like the fact that Josie played with all the Legion characters as just starting out in the academy. That was great.

You've got Jeff Wamester directing this film. You've worked with Jeff on a number of projects, including Justice Society: World War II. Why did you want to tap Jeff to direct Legion of Super-Heroes?

Because he's always there! [laughs] Me and Jeff started together on Justice Society after Chris Palmer left. I have my whole crew that pretty much wants to stick together for the whole process throughout all the films. Jeff is a great director, and I'm glad I haven't lost him to any other studio. He loves doing this stuff because every movie is different.

It's got a different storyline. Everything is a different event when you go into it. When you're stuck on a TV series, you generally have to follow through on some of the same stuff for continuity. With this, we have a lot of different avenues we can dive down, and that sparks more of the creative end for anybody. That's what's nice about it, and that's what I think he likes about it.

The Legion is huge. It's a cast of dozens when you count all the individual members. How was it working with casting and voice director Wes Gleason in assembling this roster and casting Supergirl?

With Supergirl and Meg Donnelly, Wes showed me a few of her shows and thought she even looked like Supergirl, so why not? [laughs] Some of the other characters, Wes would show me, or we'd listen to some of the voices, and it was like, "Yeah, that definitely fits Bouncing Boy and what it should be." With Arms-Fall-Off-Boy, Ben Diskin is great. Robbie Daymond, I loved his voice as Timber Wolf and the way he played it more like a guy always yelling, like Sergeant Hulka in Stripes.

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In building up this introduction for Supergirl into this vision of the DCU, how was it working with Josie to bring the Legion into that story, along with Supergirl's rapport with Brainiac 5?

I think Josie was always approaching this like it's a teenage '80s-style flick [with] comedy, but there's also a mystery involved. I think the Legion does fit into that kind of category. We also needed to have people like Supergirl, so having the growing love interest between her and Brainiac 5 was a definite because we needed to pull people in emotionally.

We always intended to start [with] Supergirl, when we first meet her, as somewhat unlikable and hard to get along with. It was about going along with this story where she learns how to be a better person, a better hero, and learn her trade. That's [the] main gist of the storyline, as far as characterization goes, to build her up into someone we end up liking.

In addition to the Legion, the Justice League is already in place, with the Flash, Batman, and Superman. What was it about having this iteration of the Justice League form off-camera before the events of Legion of Super-Heroes that appealed to you?

We needed it to feel like some years had passed. The Justice League has been around, and we're seeing elements of them, but it's not until the next two or three movies [that] we see the full force of the Justice League. In between all these stories we've approached, the Justice League has always been there, sometimes in the background or the front of the story. In this one, they're a cameo so we can build up these other characters.

Batman and Superman in Legion of Super-Heroes

I always feel like the Legion of Super-Heroes is one of the great unsung teams of the DCU. How is it introducing the Legion to a whole new generation of fans?

You know how the Legion fans are. They've all been there hardcore since they were kids. I was hoping that this would be a tribute for them, and if we bring in a bunch of new fans, all the better. It was trying to hold to what Legion fans know about these characters and how they feel about them. We didn't try to do anything outside of the qualities and characterizations that these fans grew up with. They're the ones that have always been dominant on the internet and anywhere else, making sure these characters stay true to who they are and what the Legion means to them.

That's what we were definitely following through on, trying to please the Legion fans that actually exist right now. I think because it's an introductory story, it helps anyone who has never heard about the Legion to just jump in and get a feel for it.

Directed by Jeff Wamester, Legion of Super-Heroes will be available on Feb. 7 on 4K UHD, Blu-ray, and digital HD.