Some people believed the Predator prequel would be "some extremely awakened, F-the-patriarchy kind of a narrative," according to the actress.
The 25-year-old is the star of the next Predator installment, which on August 5 became Hulu's No. 1 most-watched premiere in both film and television.
In Prey, a famous alien hunter confronted Comanche Nation warriors on Earth 300 years ago.
Midthunder portrays Naru, a competent fighter who steps up to defend her tribe from the Predator over the doubts of her people.
When the first teaser was released in June, a loud minority questioned the premise on social media.
Midthunder, 25, told PEOPLE: "People are always going to say anything, but that's just noise."
"They truly have no idea what they are talking about. First and foremost, I'm incredibly pleased with our film and think [director] Dan Trachtenberg is a fantastic director. He has created something that would make them eat their words."
"Many people, in my opinion, anticipated that our film would be some sort of extremely woke, F-the-patriarchy drama, but that is in no way what it is about."
"It's not a case of a girl opposing what males say or don't say about her. A person feels called to something, even when those who know her don't believe such to be the case."
"That is considerably more intimate and, in my opinion, more difficult for the character to handle than anything else."
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