JK Rowling's Surprising Contribution to The LEGO Batman Movie Revealed

02/13/2017 01:24 pm EST

SPOILERS for The LEGO Batman Movie ahead! Go see the movie first for the fun surprises!

Fans new that The LEGO Batman Movie took place in the same universe, or more accurately multiverse, that The LEGO Movie was set in, but that didn't mean moviegoers were necessarily ready for how that would play out in the film. After a couple of fun audio cues that hinted at other characters from other franchises existing in this same world thanks to the Phantom Zone being used to house all manner of villains, the third act really turned things upside-down, as villains from Doctor Who, Jurassic Park, and even Harry Potter were unleashed upon Gotham City with The Joker at the head of this multiversal army.

The use of those villains was a fun enough surprise, but one of their creators, JK Rowling, who created Harry Potter and all the characters therein including Lord Voldemort, was also directly involved in the film.

"We used Dumbledore in The LEGO Movie as a quick one-off joke, but Voldemort obviously playes a bigger role in this movie," LEGO Batman director Chris McKay told EW. "J.K. Rowling obviously cares very deeply about these characters, so we absolutely had to run stuff by her."

She didn't give them any negative feedback or notes, but she did offer up some real contribution that McKay would go on to use.

"The only thing she gave us was spell suggestions and things that Voldemort should say," he said, implying that her suggested dialogue made it into the film. "It was all really positive and helpful. I can't say enough good things about working with her."

Of course, Ralph Fiennes, who played Voldemort in the Harry Potter films, does a voice in this movie - but not the dark lord's, rather he voiced Alfred.

"At one point I approached the studio and asked if I could get Ralph to do both parts. But unless you're going to do a scene where Alfred and Voldemort confront each other, I didn't want something to feel like a missed opportunity," He told the magazine with a laugh. "I do remember when I was pitching him the movie, I said,'"Yeah, then all of these bad guys are going to be unleashed like King Kong and Sauron and Voldemort—' And then I stopped for a second because I realized who I was talking to."

While that didn't happen, Eddie Izzard voiced he-who-must-not-be-named and aquitted himself quite well (even if he was limited to rather PG spells this time around).

Have you seen LEGO Batman yet? Thanks to IMAX & Regal, you have the chance to win an amazing prize pack full of LEGO sets, movie tickets and more! Click here or the image above to enter. A winner will be chosen February 14th, 2017!

The LEGO Batman Movie is in theaters now.

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