Theron praises co-star Ricci

NEW YORK, Dec. 30 (UPI) -- Charlize Theron said in New York she was grateful co-star Christina Ricci was there to lighten things up on the set of the new drama "Monster."

"Christina and I laughed way too much," said Theron, who played a lesbian serial killer.

"She's an incredible actress, but she's very funny, as well."

But the "Sweet November" and "The Cider House Rules" star says she prefers working with people who don't take their jobs of "playing make-believe" too seriously.

"It's always good to have that kind of energy around where you can have a laugh about it because I can't imagine having to do something like that with someone who's serious," she explained.

"To me, it would feel like a violation. I would feel like I'm being raped or something if someone did that seriously. So, I've been very lucky to have worked with people who don't take it that seriously because I wouldn't know how to deal with that because to me, it's just like naturally silly."

Theron earned a Golden Globe nomination for her performance in "Monster" earlier this month.