In a revelation that will no doubt thrill longtime DC Comics to no end, there apparently was a Cosmic Treadmill of sorts on the set of "Justice League." Now, don't get too excited, because it's not the Cosmic Treadmill -- the fictional time-travel device used by the Scarlet Speedster -- but rather the way the Warner Bros. film accomplished some of The Flash's effects.

Star Ezra Miller pulled back the curtain during an interview to promote "Fantastic Beasts and Where to Find Them," explaining excitedly to Washington, D.C.'s Fox 5 just how he pulls off playing the Fastest Man Alive.

RELATED: "The Flash's" Ezra Miller is a Bigger "Harry Potter" Nerd Than You Are

"Sometimes they make me run, which I was outraged," he said, "because I thought, you know, playing The Flash will be great, because you can't see him running, so this is going to be easy. They were like, 'No, no, Ezra, we need you to run.'" And run he did.

"We have this enormous treadmill, I think it's called a Tumblelator, 25-feet long, goes up to 45 miles per hour, and it's bouncy like a trampoline," Miller continued, barely able to contain his energy. "It's pretty much a dream come true. And then they strap me into a harness -- we do all sorts of stuff."

However, the actor stressed that it goes beyond mere production devices; it's almost philosophical.

RELATED: "The Flash's" Iris West Expresses Concern Over Director's Exit

"What we're creating is a vocabulary," he said. "It's a vocabulary where choreography meets visual effects, and what we're trying to implement is a wide diversity of tactics of how we create these moments, and -- I don't want to give away too much -- but a lot of The Flash is his perception. So there's how fast you're moving. It's, like, you know the moment [...] when someone's eating and talking to you and they're so excited, but they're eating and they're being kind of rude and -- ptooo! -- and, like, the single crumb of food, and you see it in slow motion, almost like your brain is speeding up but it's slowing down, and so that's a lot of what we're dealing with. And we constantly get to have the geekiest conversations about physics because we're like, 'Wait! He'd be so sweaty because he's running so much, but wait, he wouldn't be sweaty at all because the sweat would evaporate the second it formed!' You know what I mean? So we just get to exist in this."

Presumably that vocabulary will carry over from Zack Snyder's "Justice League" into "The Flash" solo film,  which just last week lost director Rick Famuyiwa, who replaced Seth Grahame-Smith.

Opening Nov. 17, 2017, "Justice League" also stars Ben Affleck as Batman, Henry Cavill as Superman, Gal Gadot was Wonder Woman, Jason Momoa as Aquaman and Ray Fisher as Cyborg. "The Flash" is targeted to arrive in theaters March 16, 2018.

(via CinemaBlend)