Long before there was Harry Potter, there was Newt Scamander, a magizoologist dedicated to recording the remarkable habits of the wizarding world’s most curious creatures. Spun off from the wildly successful Harry Potter series, Fantastic Beasts and Where To Find Them follows this mythic figure through an incredible adventure in Jazz Age-era New York City.

Slight spoilers ahead.

Eddie Redmayne stars as the proud Hufflepuff alum, who’s arrived in America with a secret mission, but causes chaos when some of his secreted critters get loose. To find them, Scamander teams up with American witch Porpentina Goldstein, played by the lovely Katherine Waterston. Ahead of the film’s much-anticipated release, we sat down with this enchanting duo to discover how the world of Fantastic Beasts and Where to Find Them compares to Harry Potter, what are the cultural differences between English and American witches, and–perhaps most important–how Redmayne evolved the film’s distinctive and hilarious mating dance scene.

“There is a mating dance in the film, which was written: ‘And Newt does a mating dance,'” Redmayne began. “I was like, ‘Oh, he does, does he? Okay.’ And I worked with a choreographer that I’d worked with on Theory of Everything and The Danish Girl called Alexandra Reynolds. And she knows that I have two feet, and I am literally the worst dancer in the world.”

Together, the pair researched actual animal mating rituals, looking up videos online. From there, Redmayne and Reynolds came up with a series of imitation dances. “I sent about seven videos to (Fantastic Beasts and Where To Find Them director) David Yates, which are the most humiliating videos. If they ever saw the light of day, my life would end.” He explained they were him doing “random, just totally different mating dances…we sent the references and then actually me doing it. And then, they were always the call that I would dread. I’d just sort of sit there waiting, and (David) would go, ‘Yeah, I don’t know if that one’s a bit too–pause, dot, dot, dot–eccentric?’ Oh, okay. That means insane.‘”

Then a bit of magic came from previz animators, who urged a bit of bum wiggling was in order. “That’s really good, Let’s just do that.” Redmayne laughed. However the final touch were the mating calls that accompany it.

Waterston recalled watching Redmayne prepare, sharing, “I was in the gym one day, and he was rehearsing the mating dance. I was trying to respectfully not watch, but I could hear it. It was amazing to just hear the calls and everything.”

The Academy Award-winner admitted the calls took a lot out of him. “I had to save the calls for close-up though, because after you do more than one you totally lose your voice,” he confessed. “I wanted to give it everything, and totally commit.”

“It ain’t easy,” Waterston commiserated. “He makes it look easy, but it ain’t easy.”

Let’s cross our fingers that Redmayne might overcome his embarrassment in time for Fantastic Beasts and Where To Find Them DVD special features to be pulled together!

What was your favorite part of Fantastic Beasts?

Image: Warner Bros.