Before Ezra Miller’s career trajectory goes supersonic in “The Flash,” he’s still moving at a more deliberate – if still high-profile – pace in “Fantastic Beasts and Where to Find Them.”

The energetic young actor takes on the role of Credence Barebone, a troubled, brooding, bowl-cut presence within the No-Maj clan headed by anti-wizard crusader Mary Lou Barebone, who crosses paths with Newt Scamander during his visit to America.

A fan of both the fantastical writings of J.K. Rowling and the high-velocity comic book adventures of Barry Allen, Miller revealed the secrets behind his entry into two highly coveted roles.

When you came in smiling and happy, we thought, “That can’t possibly be the person that I first saw on screen in this film.”

Ezra Miller: It was me even between takes, though … It’s interesting because in the script, Newt is described as Buster Keaton-esque. And so I felt like I was maybe treading on his territory a little, but I’ll tell you in earnest that I did use Buster Keaton as a reference. I think for Newt, it was more the quirkiness of Buster Keaton’s body language. For me, there was something about the way that sadness came through the stillness in Buster Keaton, that seemed appropriate for Credence.

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I had a few reference points from popular culture, also. Daniel Johnston, this artist that I’m a big fan of, I liked his physicality. Really, the most important models for Credence were these people who I had the privilege of talking to who had survived circumstances parallel to the ones that Credence endures in the film. … Even specifically speaking to a couple people who had survived abuse in foster care, who will remain anonymous for the purpose of these interviews.

FANTASTIC BEASTS AND WHERE TO FIND THEM

Did J.K. Rowling talk to you? Did you see her at all while you were filming this?

So I was very lucky – Felix Felicis lucky – to meet her, one time, one day on set, midway through production. I was just so overcome with emotion to be in her presence. I didn’t manage to articulate many questions or say anything intelligent. I just was trying to keep my mouth closed and my jaw from going completely slack.

So you didn’t ask her to autograph your script?

I forgot! It completely slipped my mind. Then afterwards you’re like, dang it! What a missed opportunity.

Do you perceive your character as a nice guy who’s been twisted by his abuse into something that he’s really not? Or do you see him as a victim, somebody we should feel pathos for?

My approach to Credence was someone who never got the love that they needed, and who was also subject to this sort of violent indoctrination that made him believe that he was bad. And that stops him from allowing the truth of who he is to rise to the surface.

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It seems like the character itself is sort of an exploration of the results of that type of trauma, and that sort of repression. What happens when we don’t let ourselves be ourselves can actually be pretty sad and scary.

Seeing how your character’s an outsider, is that something you can relate to when you were younger?

Yeah, sure. I experienced my fair share of bullying and teasing as a youngster with strange interests, with a speech impediment when I was a kid, which made me an easy target. ... Yeah, and also, when I started going through puberty and was having confusing feelings about wanting to kiss people, and not all of them being girls, yeah. There were moments in my life where I felt ostracized from my contemporaries or from my peers.

Those times are really painful, but of course also very formative because they prompt us to step outside of society, and to look at the world with fresh eyes, which is why I think so many of our great minds have been ostracized folks and disenfranchised people over the world.

What did the “Harry Potter” books and movies mean to you as a kid? And did you ever have moments when you were on the set where you were going, “Oh, my God? How did I ever get here?”

Every single day. I was reading "Harry Potter and the Sorcerer’s Stone" because it was the American edition, [given to me] by my father when I was seven. And I just grew up loving the books so much. I’ve read them all so many times. I was really a “Harry Potter” kid. I listened to the audio books constantly. The audio books kind of became my retreat and my sanctuary.

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So in those years of bullying, I was just referring to, I would actually come home from school and listen to “Harry Potter” for a few to several hours every single day, while I ate instant ramen. It was a bit of a sad time in my life. But you do what you have to to get through times that are hard. To have a resource like these stories that remind you of what’s good in the world and in yourself, yeah, it was helpful to me in ways I can’t fully understand I’m sure.

FANTASTIC BEASTS AND WHERE TO FIND THEM

Was acting then at that point a form of empowerment to get out of your bullying?

Yeah. It felt like so clearly what I had to be doing from a young age. So that was also a principal form of solace, was the work, which I was doing from a young age. Similar to being fanatically involved in some sort of fiction is the process of becoming a character. It’s a continuation of the make-believe that we all play as children.

What do you want young viewers to know about this movie?

I just think that everybody should go see it. The only thing I want them to know is that, for me, as someone who was a young “Harry Potter” fan, this movie lives up to all of my expectations. Clearly, I’m a bit of a biased party because I’m in the movie, but I would like to think I was a rather critical viewer despite that fact, and this film exceeds expectations.

As a fan, what surprised you about this presentation of the world, as someone who’s read the books that you might not have seen? Something that you’re like, “Oh, that’s how that happened"?

I just think it’s fascinating the way that some of the differences between England and the United States are explored, but through the lens of the magical community. So the idea that the international statute of secrecy is much more of a hard line in the United States, because the persecution of people who don’t fit into the status quo is more heightened really resonates with me.

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The 1920s in the United States is an important time, especially the late 1920s, for us to look at right now in U.S. history, because there was a rise of fascism, sort of Death Eater behavior in the 1920s. Like, the Ku Klux Klan saw its height historically in the late 1920s. There were all of these ideologies, new ideologies, new people coming into the United States, and this unfortunate tendency for human beings to fear, reject, and act out violently towards what is unknown to them, was at a height in U.S. history in the late 1920s.

So I think it’s fascinating that she chose this time to explore through the lens of the Wizarding World. Especially in the time we’re in when we see Voldemort on TV every day.

flash-ezra-miller

You are also going to be The Flash for Warner Bros.' new film. The search in on for a new director now.

Yeah. I’m confident that Warner Bros. should be able to find a director.

Do you see a connection between these two characters?

I see connection between all people. I think that as, you guys know Venn diagrams? If all of humanity is a Venn diagram, there’s that little area that’s common to all of us, and we are all interconnected. We all derive energy from this spaceship Earth that we live on. We’re all one. We’re all connected.

Specifically, I would say that I find it interesting that Barry Allen and Credence Barebone both have trauma and psychological disruption in their formative years, and that they deal with it very differently. I would posit the theory that at least in the parts of the stories we’ve seen, Barry Allen might deal with it slightly better than Credence, but the circumstances are very different.

Were you into comics and superheroes as a kid?

Big time. From a young age, I was a huge, particularly a Batman fan. But loved the Justice League, watched a lot of the cartoons, read comics. Yeah. I used to say, when I’d go to Forbidden Planet, I used to say to my father, “When I have money of my own, I’m going to spend it all on Forbidden Planet!” I did not anticipate that that money would be coming from a comic book role in a movie. And now, I can get some free action figures if I play my cards right. So my whole plan has really fallen apart.

Starring Eddie Redmayne, Newt Scamander, Katherine Waterston, Dan Fogler, Alison Sudol, Ezra Miller, Samantha Morton, Jon Voight, Carmen Ejogo and Colin Farrell, "Fantastic Beasts and Where to Find Them" opens today nationwide.