Reneé Rapp is ready to embody Regina George once more! The “Sex Lives of College Girls” actress shared with ET that she’s been cast as the queen bee in the upcoming “Mean Girls” musical movie, after playing the same role in the Broadway musical.

“I’m doing it! Woo hoo!” she gushed to ET’s Denny Directo, before revealing how she found out she landed the role.

“I was excited. Man, I was excited,” she recalled. “I was on the treadmill. I was at home and I was walking and I just finished a day of the ‘College Girls’ filming and my agent called me.”

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“My mom rushed into the house… She was like, ‘Renee!’ ’cause she obviously knew ’cause everybody in my family and on my team is in cahoots. Everybody knows everything before I know it,” Rapp continued. “I was so stressed ’cause I was [like], ‘What’s going on?!’ I thought I was in trouble and then I wasn’t.”

When it comes to what fans can expect from the movie, Rapp teased, “It’s gonna be a very exciting, authentic take on what ‘Mean Girls’ is and what ‘Mean Girls’ means to us as kids.”

“That’s what I think is so cool, because I feel like a lot of things get remade and… it feels like, ‘OK, why are we doing this?’ But for me, it’s so sick because ‘Mean Girls’ was such a big part of my childhood, so I’m like, ‘Oh, so this is what this meant to me and my generation,'” she said. “It’s a huge impact. What [writer] Tina [Fey] did is big.”

As for what she has to say to Rachel McAdams, who originated the iconic role in the 2004 film, Rapp joked, “I love her. I love you, Mommy, in a respectful way.”

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Not only did Rapp’s Broadway stint end up landing her a role in the highly anticipated movie, but it also “absolutely” prepared her to embark on her first headlining tour, the “Everything to Everyone Tour”, which kicked off Tuesday at The Troubadour in Los Angeles.

“It was the coolest thing that I could’ve ever done. I don’t think I got to process it in the moment or experience it to its fullness because I was young. Also it was my first job and I was so scared,” Rapp told ET of Mean Girls on Broadway. “… It set me up so well for this moment. I’m so grateful for everybody who even took a chance putting me on that project.”

“I know that a lot of people were coming to my shows found out about me through ‘Mean Girls’, so it’s really, really weird,” she added. “It’s really weird. It’s good, though.”

Though her Broadway past helped prepare Rapp for her tour, she admitted that she’s “terrified” of performing her own music.

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“It feels like it’s going to be different,” she said, before sharing what fans can look forward to seeing at the shows. “I think you can expect pretty much a sum of who I am… It just feels like a big hang.”

Rapp’s tour follows the November release of her debut EP, Everything to Everyone.

“It was the only time that I felt understood or that I communicated my feelings properly in my entire life,” Rapp said of making the EP, before teasing what fans can expect from her debut album, which is currently in the works.

“The thing I love about the album that we’re sorta working through is that it has a lot more influences production-wise from the music I grew up listening to,” she said, “so you’ll feel a lot more of my personality in the production because I know who I am.”

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