Millie Bobby Brown has been someone to watch since her breakout role as Eleven on Netflix's Stranger Things. Her feature film debut is in Godzilla: King of the Monsters, in which she plays Madison Russell, who becomes embroiled in the conflict between those who want to exploit the Titans and those who believe Godzilla can save humanity.

At a press conference to promote King of the Monsters, Brown touched upon her training for the role, her favorite Titan, her method of choosing projects, and gave a small tease for Stranger Things 3.

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"Basically, when you watch the movie, I have a lot of running, and running takes a toll," she said. "I needed to prepare rationally, so I could run uphill and then make sure that I wouldn't be out of breath before I got to the top of the hill. First time around, I was like [gasps for breath]. I just kept practicing. I was training every day. And so I totally trained physically for the role. And how is it performing with something that isn’t there? You just do it."

While O’Shea Jackson Jr., who plays Chief Warrant Officer Barnes, has been a Godzilla super-fan since childhood, Brown admitted she wasn’t, at least not initially.

“Which is a good thing, because my character isn’t," she said. "My character is just a teenage girl who's just learning about Godzilla and the Titans as she goes along. She doesn't really know how she feels about him. But, I think that her love and affection towards him rose into the movie, and also in Godzilla vs. King Kong.”

Godzilla: King of the Monsters

The actors didn’t know how Godzilla and the rest of the monsters would be until they watched the film. Brown's reaction to the unknown was that she “was nervous.”

“Because I do that with everything," she explained. "I just go into everything really negative. ... I don't like to be let down. So, I went in there with the mindset like ‘it's gonna be fine.’ It's really just, like, I trust everyone else but myself. And there are many things I'd like to change about my performance just because I'm just like that, but I really liked the movie. There's so much human emotion.”

Answering questions about which Titan, besides Godzilla, they find the most intriguing, Jackson said Rodan, to which Brown jokingly replied, “That’s so incorrect.”

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“I think Mothra, because she's the only girl," she said. "She's such a hero. She’ll just be like, ‘What up, guys, who needs me?’ She’s so gorgeous.”

Brown said she has received a number of film offers since the success Stranger Things. Elaborating on how she chooses her roles, she talked about how her sister reads the scripts first. “I get offered comedies, thrillers, horror, but it doesn't matter about the genre for me," she said. "If I feel like I have a connection with the character, then I'll do it. I'm actually filming Enola Holmes with Legendary this summer. It’s [about] Sherlock Holmes’s little sister. It’s a series about who she is and her journey.”

Millie Bobby Brown Vera Farmiga Godzilla King of the Monsters

“I really want to be part of the creative process," Brown added. "I think it's so important to have us and to inspire young people to understand that there's no boundaries, no age to what you can accomplish.”

The cast had a great time working with director Michael Dougherty, who is a big Godzilla fan. Discussing her appearance on set, Brown said, “One of the things I loved is he stayed true to the story. And I think that it's important especially in such a legacy you don't want to just go AWOL with a story that people absolutely love and cherish and wait for. Before I was on board, I went with a meeting with [Michael], and I think he said, ‘Vera Farmiga is attached to the project,’ and then for Vera, he was like, ‘Millie Bobby Brown is attached to the project.’ None of us had been attached to the project!”

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“One of the things I loved is that from the very beginning, he knew what was going to happen," she added. "He didn't change a thing about it either. Our scripts never changed drastically. … He knew what every monster is going to look like, he had everything planned, all the artwork, and immediately I was like, ‘Wow.’ Like, if he knows what he's doing, there's no questioning what he's doing.”

Brown wasn’t able to say much about Stranger Things' anticipated third season. “Season 3 is coming out on July 4, and we're so excited for everyone to see it. We've worked really hard on it. And we filmed [Godzilla: King of the Monsters] two years ago, right after we were filming Season 3. Season 3 is, you know, it's bigger, it's better and stranger. ”

Directed by Michael Dougherty, Godzilla: King of the Monsters stars Vera Farmiga, Ken Watanabe, Sally Hawkins, Kyle Chandler, Millie Bobby Brown, Bradley Whitford, Thomas Middleditch, Charles Dance, O’Shea Jackson Jr., Aisha Hinds and Zhang Ziyi.