EXCLUSIVE: Elizabeth Banks on Her Transformation for 'Power Rangers'

Elizabeth Banks is nearly unrecognizable in the upcoming Power Rangers reboot, and she told us the hair and makeup process for the film was even more complicated than it was for her Hunger Games character, Effie Trinket.

"Rita had prosthetics!" Banks told ET's Cameron Mathison. "I spent a lot of time in the chair basically naked. Every time I went to set, it was like a big reveal."

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The Emmy-nominated actress plays the villain, Rita Repulsa, in the film, which required four hours of makeup, face prosthetics, fake teeth and a stretchy green body suit to achieve the sexy, evil look.

The role is meaningful to Banks as the mother of two fervent Power Rangers fans -- sons Felix, 5, and Magnus, 4 -- but she admitted that it might be a while before they're allowed to watch the movie.

"I don't want them to be afraid of their own mom, so I don't know if they're going to see this in the theater," she said. "They're still little."

In fact, Banks said she "totally freaked them out" one time when she Facetimed with them from the set while still in costume.

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The reboot follows "five ordinary high school kids who must become something extraordinary when they learn that their small town of Angel Grove -- and the world -- is on the verge of being obliterated by an alien threat."

"Chosen by destiny, our heroes quickly discover that they are the only ones who can save the planet," the synopsis continues. "But to do so they will have to overcome their real-life issues and band together as the Power Rangers before it is too late."

The new cast includes five newcomers: Red Ranger Jason (Dacre Montgomery), Blue Ranger Billy (RJ Cyler), Yellow Ranger Trini (Becky G.), Black Ranger Zack (Ludi Lin) and Pink Ranger Kimberly (Naomi Scott).

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Saban's Power Rangers opens March 24.