Kristen Stewart's Vampire Transformation "Scared" Her 'Twilight' Co-Star

Kristen Stewart has been waiting to play a vampire in the Twilight films for a long time and now she finally has her chance! So how is she doing? Apparently well, since she scared her co-star Elizabeth Reaser!

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Elizabeth Reaser has played vampire Esme Cullen throughout the franchise so she's used to being around a group of vampires, but Kristen takes it to a new level!

"There's been some really cool stuff in the Cullen house with Bella," Elizabeth told MTV News. "There's been some interesting transformations happening."

So how is Kristen doing pulling off her vampire transformation?

"She scared me a little bit on Thursday, I'll be honest with you," she said. "Because when vampires are newborns, they're stronger than any other vampires, so for a second there I thought, 'This might not end well. She's looking pretty pissed right now.' It was great."

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And Robert Pattinson and Peter Facinelli have had a similar reaction to Kristen's vampire portrayal.

"It's really funny, it's like a completely different environment on set when she's a vampire and when she's not," Rob previously told MTV News. "I think she's going to do it really well."

"She's doing really well. She looks fantastic," Peter also previously said. "For some reason, once they put those contact lenses in, you look very statuesque."