The Insider.com

Paranormal Activity 3 scared up an estimated $54 million this weekend, setting the record for best horror movie opening ever. An accomplishment that has left everyone -- from the industry to the stars -- stunned. "It's pretty incredible," star Lauren Bittner told TheInsider.com this morning. "I'm still in a state of shock."

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Ditto for audiences, who have almost unanimously dubbed Paranormal Activity 3 the franchise's best release to date -- a development Lauren believes lies in the old-school scares. "Everyone can relate to being in a house alone and thinking you heard something downstairs. Your imagination gets the best of you and suddenly anything is possible," she says. Spoilers from this point forward

Like, say, an entire kitchen falling from the ceiling? "Yeah, that could alarm a person," Lauren laughs. "Filming that was incredible – it was done totally, 100 percent on set. I can't tell you how we did it, but the guys behind the scenes were amazing. That created such a loud noise, I was really terrified. It produced such an authentic moment."

And while that moment has left audiences talking, people also can't stop buzzing about how many of the trailer's most memorable moments -- the girls playing Bloody Mary, Julie being pulled into the bedroom by Toby, a psychic getting manhandled by the spirit -- were not in the finished film. That left me wondering, did they intentionally film footage just for the trailer?

"Not really," Lauren tells me. "This franchise is lucky because it can afford to shoot and edit at the same time. We filmed for quite some time and it becomes a trial-and-error environment. They see what's working and what isn't while filming is going on, so a lot of what you saw in the trailer was very good on its own, but within the context of the film, just didn't fit right."

What did mesh from the jump was Lauren's relationship with her film family. "We all sort of clicked from the very beginning. Chris [Nicholas Smith, who played Dennis] was so wonderful to work with. So ready to improvise and try everything out. And then the children were so amazing. I fell completely in love with them and really wanted to protect them by the end."

Speaking of that ending, what did Lauren make of the nontraditional climax that saw the family leave their home and journey to grandmother's house, only to find an even scarier sight? "Wasn't that crazy?"

"I thought the change in environment was extremely effective," Lauren says. "Because even though you don't know what's happening at the first house, it starts to feel like 'home' – that's why the oscillating fan was so brilliant because it helps the audiences get to know the rooms so well that by the time we get to grandmother's house, it's totally new territory. You're discovering the new rooms step by step and following these characters we're familiar with in a totally unfamiliar place."

It was there that Lauren filmed one of her favorite scenes: Julie's death. "When the camera finally gets to the top of the stairs and realizes she's not on her feet? I thought it was so exciting and I hope people feel the same way. It's hard because with this particular franchise, fans have expectations and have already started to fill in the blanks and connect the dots. So much is built on what they want, so I just hope we didn't disappoint." I think $54 million worth of moviegoers would say they didn't.

Paranormal Activity 3 is now playing.