Though she never got to meet rock and roll legend Elvis Presley before his death in 1977, the 33-year-old actress exclusively told E! News that watching Butler's portrayal of her late grandfather in the new biopic Elvis was "really emotional."
"I didn't know what to expect," she said. "And I think the moment I saw him, I don't want to be a spoiler alert, but there's a moment in the first kind of five minutes that's very powerful with Austin, and I kind of, you know, I started crying. It was really intense."
The Zola star—who recently attended the film's Graceland premiere alongside mother Lisa Marie Presley and grandmother Priscilla Presley—also applauded Butler's dedication to the role, saying, "It's not something that I think you see very often with young actors and it's a wonderful film. Austin is incredible."
Keough will soon follow in her grandfather's musical footsteps, playing the titular, fictional rock star in Prime Video's upcoming Daisy Jones & The Six series. In the meantime, fans can soon watch her in another Prime show, The Terminal List, which premieres July 1.
Keough stars as Lauren, the wife of Chris Pratt's James Reece, a Navy SEAL who discovers that a deadly mission may have been more than just a mistake.
"I got to speak with SEAL wives," she told E! News about preparing for the role. "I spoke to a couple of women and that was probably the most helpful thing for me, just kind of wrapping my head around the kind of mindset that they're living in constantly."
Balancing happy family moments while knowing your loved one might not return was a concept Keough described as a "challenge to figure out," but one she sympathized with.
"That's a very hard way to live," she stated, "and they kind of tried to enjoy the moments they had with their family and I thought that was really beautiful and that when they would come home, that it was always kind of a big celebration and trying to stay in the moment knowing that they're going to have to leave again."
Elvis premieres in theaters June 24, and check out The Terminal List on Prime Video July 1.
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