[article id="1657159"]Leighton Meester's dorm-based thriller "The Roommate"[/article] received a warm welcome from moviegoers during its debut Friday.

The "Gossip Girl" star's turn as an accommodating turned obsessed roomie who goes all crazy-pants on Minka Kelly's unsuspecting character raked in $6.4 million when it arrived in theaters. Perhaps part of the film's draw is the fight scenes -- fist-flinging showdowns which Kelly said the actresses worked hard to imbue with a sense of it's-going-down authenticity.

"We worked really hard to make sure it looked like a real girl fight," she explained. "I Googled 'girl fights' on YouTube, and we made sure it was messy and hair was everywhere."

Kelly added that the starlets didn't bother faking the combat, leaving their Hollywood images behind and lobbing actual punches. "We fought to kill, because unfortunately, when girls fight, they fight to kill, and that was very true and real in our fight. We did our own stunts. We were pretty banged up by the end of it," she admitted.

The [article id="1657297"]James Cameron-produced adventure "Sanctum"[/article] debuted in the second place. The flick, which treads familiar Cameron man-against-the-elements territory as it follows a team of explorers who get caught in a labyrinthine underground cave system following a dramatic storm, scored $3.5 million.

[article id="1656271"]"No Strings Attached[/article] slipped to third place. The casual-sex rom-com, which features Ashton Kutcher and Natalie Portman, scored $2.9 million on Friday. The haul kicks the film's box-office bank to about $46.3 million.

Still riding the boost from its boatloads of Oscar love, "The King's Speech," kicked off the weekend in fourth place. The film made $2.3 million, a figure that pumps the project's total estimated tally to $78 million.

Screen legend [article id="1656871"]Anthony Hopkins' latest flesh-crawling flick, "The Rite,"[/article] spent Friday in fifth place, with $1.9 million. The movie's total estimated gross now stands at around $20 million.

Check out everything we've got on "The Roommate," "Sanctum" and "No Strings Attached."

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