PARK CITY, Utah — Ever since Kristen Stewart spilled the beans at the People's Choice Awards that she had been filming "Breaking Dawn" as a vampire that day, it's all we can think about when we get the chance to talk to one of her "Twilight Saga" co-stars.

Elizabeth Reaser, who plays Esme Cullen in the film franchise, teased at the Sundance Film Festival this week that there have been some crazy vampire scenes on set recently.

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

Sounds to us like director Bill Condon has been filming the famous "Breaking Dawn" birthing scene, and that Reaser got a chance to see Bella's transformation into a vampire. Producer Wyck Godfrey already shared that the birthing scene will be shown from Bella's perspective to keep with the film's PG-13 rating, but as Reaser witnessed the whole scene unfold, what was her impression of Stewart's transformation?

"She scared me a little bit on Thursday, I'll be honest with you," Reaser 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."

Reaser's praise of Stewart's performance as vampire Bella matches with what co-stars Robert Pattinson and Peter Facinelli had to say about it at the Golden Globes. Pattinson told MTV News it felt like Stewart "wanted to do it the entire time."

"It's really funny, it's like a completely different environment on set when she's a vampire and when she's not," he said. "I think she's going to do it really well."

In the books, Bella becomes much more confident after transforming into a vampire, so it's fitting that Stewart is coming into her own with the role. Facinelli jokingly credited vampire contact lenses as the real reason Stewart is doing so much better.

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

Check out everything we've got on "The Twilight Saga: Breaking Dawn - Part 1."

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