Hathaway spoke about working alongside Leto at the premiere of their new Apple TV+ series Thursday.
ET's Lauren Zima spoke to Hathaway at the premiere of her new Apple TV+ series, WeCrashed, where she opened up about working alongside the consummate method actor.
"He's so sweet. He's really playful and we just make each other laugh. We have a really gentle thing," Hathaway gushed. "The little that I know about Jared, is that he cares about what he does, body and soul, so much. And I'm the same way. So, to be able to connect like that over a shared passion, something that we both really love giving ourselves fully to -- in a way that I get it, it's unusual -- it was really, really special. I feel really lucky that he was my partner in this."
Leto wasn't the only one to commit to his character. Hathaway started a whole new diet to play the role of Rebekah Neumann, the wife of WeWork CEO, Adam Neumann (Leto), in the series, which not only tells the story of the company's rise and fall, but the love story at the center of one of the world's most valuable startups.
"I didn't commit to it. I just found myself there in the end," Hathaway said of her raw vegan diet. "She kinda took hold."
It's not all bad though, with Hathaway joking, "I love it -- until I don't."
While there were rumblings that the Devil Wears Prada actress got Leto to break character to say the iconic House of Gucci line, "Father, Son and House of Gucci," Hathaway maintained that the 50-year-old did not break character, no even once, while filming the limited series.
"No!" She exclaimed. "He never broke. Never broke. Not even once. Not for any second. Not even for that one. That was one of the most impressive things about it, was, as I mentioned, split in three like a horcrux, and then came back together, and then responded as Adam."
All in all, Hathaway said she feels "so crazy lucky" for the opportunity to be a part of the latest in Apple TV+'s lineup.
"I'll tell you how I feel, is so lucky, so crazy lucky. I'm grateful to be here. I'm grateful for the opportunity, and I'm grateful for the team that got me all, lookin' like this," Hathaway, who was sporting a bright blue dress, which featured asymmetrical cutouts, with a black bralette peeking through the left side of her dress, said.
See Hathaway and Leto in WeCrashed, when it starts streaming on Apple TV+ March 18.