Oscar-winning actor Eddie Redmayne still finds it difficult to believe that he's starring in a new series of five movies that are part of the Harry Potter universe, starting with Fantastic Beasts and Where to Find Them. But he loved diving into that world, especially since J.K. Rowling was able to describe everything in so much detail. 

Eddie Redmayne in Fantastic Beasts and Where To Find ThemEddie Redmayne in Fantastic Beasts and Where To Find Them

"When I was prepping," he says, "I met Jo Rowling, and what's so amazing is that her imagination is so full and thorough. It's so encyclopaedic of her world! We had an hour together and I sort of asked her about 800 questions. There was no small talk. I just said, 'Right, tell me about Newt.' I've played real people with historical information available about them, like Stephen Hawking [in The Theory of Everything] and Lili Elbe [in The Danish Girl], and there was a lot of intense research around those roles. But then came Newt, who is of course a fictional character. So Jo became my research!"

What he discovered about Newt Scamander was that he's more comfortable with animals than with humans. "He's a man with a passion, and his passion is animals," Redmayne laughs. "He disconnects with people. People seem to misunderstand him, and he doesn't know why, but he's also not particularly interested in why. He has his own relationship with his animals."

More: Read a review for Fantastic Beasts And Where To Find Them

To get into the head of the character, Redmayne went on a tracking course. "This guy showed me how to live in the wild," he says. "I learned some amazing things, like how you see through peripheral vision and the different types of plants that can be used as remedies, with spit in your hands! And one of the main routes in for me was finding the way Newt moves. You're trying to be absolutely silent."

But what impressed him the most was the incredible detail in the film's sets. "I've done CGI films where the whole world is green, and you have no context," he says. "But what's amazing with this is the amount of puppeteers or dancers or people you work with. And they will then not be there on the screen."

Now that the film is opening to the public, Redmayne is feeling a bit apprehensive. "Each time you put a little thing like that out into the world, it feels nerve-wracking," he says. "The weird thing about filmmaking is that you make films as a team and together, you care about every bit that goes out. You care what people think. I care."

Watch the trailer for Fantastic Beasts And Where To Find Them: