There’s one thought that many of us probably have while watching pop culture mashup extravaganzas The LEGO Movie and The LEGO Batman Movie: How much did they have to SPEND on all of this? Not only is it packed with classic Batman references, The LEGO Batman Movie features an even more impressive rogues gallery of properties than the first in its insane latter half, which involved a lot of secrecy and a lot of lawyers. [Be warned: this post contains major SPOILERS for The LEGO Batman Movie.]

The main plot of The LEGO Batman Movie revolves around the Joker’s plan to get Batman to admit that he’s his greatest foe. Without going too deeply into the mechanics of it all, Joker gets himself banished to the Phantom Zone, a jail for all of the greatest villains in history. Joker lets them all out, and they begin to terrorize Gotham. Director Chris McKay spoke with Entertainment Weekly about the process of getting the rights to characters like Voldemort, Sauron, King Kong, and the Gremlins, and how he got the idea to fill the last half of the movie chock full of villains.

The Joker needed to up his game and prove himself, and we talked about this being the Joker’s big romantic grand gesture. So in order to do that… I loved the [1978 Richard Donner-directed] Superman and the idea that the Phantom Zone, in our world, could possibly house all of the villains from other LEGO universes. It’s almost like Cabin in the Woods. Or, in Last Action Hero, when Charles Dance says, I can go into all these movies and I can bring out Jack the Ripper or King Kong. When I was younger, watching that movie, I was somehow expecting a scene between King Kong and Arnold Schwarzenegger, and I was always bummed it didn’t go there. [Laughs.] But in our world, we can do something like that and unleash all these characters into Batman’s world.

There were a few villains who didn’t make the cut.

I would have had Kathy Bates from Misery, and [Sherlock Holmes nemesis] Moriarty, and at one point I pitched Daniel Day-Lewis’s character from Gangs of New York and David Carradine from Kill Bill. At a certain point, though, you have to weigh what characters the kids going to get. In LEGO, it’s sometimes hard to get a really quick interpretation of something. I was already worried that we weren’t doing enough with some characters. Also, at one point, we did put HAL from [2001: A Space Odyssey] into the movie, but it was a tough read. Maybe in future movies, we’ll try to bring more characters in.

He also spoke about licensing the characters and how complicated it all was.

You need an army of lawyers and producers who are willing to run around and do all the hard work of finding out all the rights-holders. Fortunately, Warner Bros. made a lot of those movies, but for others, we had go to out and get them. I wanted characters from all over the world. I wanted Daleks. I wanted stuff that has a history and is time-tested, like the Wicked Witch. And I hope people love Gremlins as much as I do. And Sauron. But even for the actual Batman villains, even though that’s all [property of] DC, someone still has to go out and find it, you know, the guy that wrote Gentleman Ghost into the issue where he first shows up. I definitely kept a lot of coordinators, producers, and lawyers busy on this movie. I’m sure I drove people crazy.

McKay gushed about how fun it was to work with J.K. Rowling on Voldemort.

We used Dumbledore in TheLEGO Movie as a quick one-off joke, but Voldemort obviously plays a bigger role in this movie, and J.K. Rowling obviously cares very deeply about these characters, so we absolutely had to run stuff by her. But honestly, there were no notes. The only thing that she gave us was, like, spell suggestions and things like that that Voldemort should say. It was all really positive and helpful. It was never ‘I’m uncomfortable with that.’ I can’t say enough good things about working with her.

He also revealed which of the secret voice cast he was most excited about.

Being able to cast Billy Dee Williams [as Two-Face]. As a kid, when I saw the Tim Burton Batman movie, I knew enough about all the characters that when I saw they cast him as Harvey Dent, I was so excited because I thought they’re going to play this long game where in the next movie or two movies down the line, he would show up and have this great arc from good guy to bad guy! And then when the third movie came around and not only had the cast changed, but there was no arc — it’s just suddenly Tommy Lee-Jones as Two-Face — I was really bummed out. So to be able to cast somebody in that way was great. I mean, the first thing he said when he showed up on set was, ‘Oh, I finally get to play the role I was hoping I was going to play.’ I felt really proud about that. It felt good to fulfill something from my childhood that always felt like a missed opportunity or just a bummer.

The LEGO Batman Movie is currently in theaters. You can read our glowing review here.

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