ET spoke with director Baz Luhrmann at the Oscar nominees luncheon on Monday.
"I was not gonna make the film unless I found someone who could play Elvis," he recalled of the pre-production process. "I didn't really think I could."
Everything came together when he found Austin Butler, who devoted himself to learning The King's songs, mannerisms, and, of course, his iconic voice. However, Luhrmann said the most "nerve-wracking" screening of his entire career came when he sat down with Priscilla to show her the film for the first time.
"[Priscilla] was quite cynical about how this young kid could, in fact, manifest her husband," he shared, noting that the family has had their share of "disappointments" when it comes to portrayals of Elvis onscreen. "I remember Priscilla said, 'I know I was hard on you,' she wrote me an email... She said, 'Every wink, every move, if my husband was here he would say, 'Hot damn, you are me!''"
"She said, 'How did he know about Elvis' rage, his stillness, his inner life, his complex inner life?'" he added. "Because that's not out there. That's not in a biography."
Ultimately, Luhrmann said, Butler is deserving of all the acclaim he's received so far.
"I think you can't overstate the level of acting achievement for Austin Butler," he raved. "I've been around it a long time and even I'm a bit mystified by what he achieved -- and I was there!"
The actor landed his first-ever Oscar nomination last month. Butler has been effusive about thanking the Presley family at every given opportunity this awards season and he paid special tribute to Lisa Marie, who died at the age of 54 on Jan. 12 -- less than two weeks before nominations were announced.
"[This role] seemed as though it was this impossible mountain to climb in front of me. There were so many pitfalls and so I just was focusing on one step at a time," Butler told The Hollywood Reporter. "And that’s why those moments when Lisa Marie and Priscilla [Presley] got to see the film and then I first saw them after… nothing I would do would ever top that. And especially with Lisa Marie not being here with us. I just wish she was here to celebrate today with us."
He said that Lisa Marie "was the most straightforward and supportive person," adding, "I know from all the times that we got to celebrate together how we would celebrate today, you know, and I wish she and Elvis were here to get to experience this time."
Butler finished by reflecting on what her support meant to him as he put so much time and effort into bringing her father back to life onscreen. "The thing I’m most grateful for is that I was able to spend the time that I had with Lisa Marie, and also the time that I had in getting to live for three years exploring the life of her father," he said. "When I see moments like today or when I feel moments like today, I have to really take a second to go, 'Okay, this is this is something to be really grateful for.' But nothing compares to that moment I looked in her eyes after she first saw the film, where she told me how much it meant to her. I’ll really cherish that for the rest of my life."
The 95th Academy Awards, hosted by Jimmy Kimmel, will be handed out live at the Dolby Theatre in Los Angeles, California, on March 12 starting at 8 p.m. ET/5 p.m. PT on ABC. In the meantime, stay tuned to ETonline.com for complete Oscars coverage.