The Oscar winner first discussed the job with Lana Wachowski, the transgender co-director of his sci-fi film Jupiter Ascending. He then met with trans activists and April Ashley, an 80-year-old transgender woman who once modeled for Vogue.
"The first thing Eddie said to me was, 'Oh, April, before I can say anything to you, my father sends his love and tells me to say thank you for all the lovely dances you used to have together at [the 1960s London nightclub] Tramp,'" Ashley says in the new issue of Out magazine. "I was terribly amused."
The Danish Girl, based on David Ebershoff's book of the same name, tells story of Lili, who is believed to be the first person to undergo gender reassignment surgery in 1930. Alicia Vikander plays her wife Gerda Gottlieb. The movie also reunites Redmayne with his Les Misérables director Tom Hooper.
Redmayne has learned a lot since he first signed on for the movie. Playing Lili has taught him that gender is "fluid. And also that it needn't be labeled."
He was in New York when Caityln Jenner's Vanity Fair cover was released. "I was reading The New York Times, and all of the op-ed pieces that were being written about it," Redmayne says. "The dialogue was so rich and full, with everyone having opinions. Then I came back and saw the trailer for the film."
He praises Jenner for her visibility. "I absolutely salute her courage," Redmayne says. "Hers is a very specific story, and it's one that shouldn't stand for everybody. But it is amazing what she's gone through and how she's done it."