Eddie Redmayne had been preparing for 'The Danish Girl' for three years.
The 33-year-old actor has revealed he had a fairly extended amount of time to research for his role as transgender artist Lili Elbe compared to when he portrayed Stephen Hawking in 'The Theory of Everything'.
He explained: "With 'Theory', I was so scared by it that it forced me to step up and request the things I needed - vocal coaches, movement coaches, specialists. I had four months to prepare. For 'The Danish Girl' I had three years."
The Oscar-winning actor also admits, through rehearsing for the part, he has learned that he fell into the "clichés of ignorance" as he didn't realise gender and sexuality wasn't "related".
He explained: "I fell into all the clichés of ignorance. I didn't realise that gender and sexuality weren't related. I confused the terms transvestitism and transgender.
"But what's lovely is, the second you understand the difference, you see how gigantic it is and how important it is that we educate ourselves."
And Eddie admits he has learnt a lot about women from his role in the film, which is due for release early next year.
He added to Details magazine: "Just walking onto a set filled with men, watching the difference in how you're treated, or the scrutiny ... the gaze was overwhelming.
"A lot of the women I worked with said, 'Yeah ... welcome to our world.'"