THE LATEST ON Celebrity Josh Hartnett

Scarlett Johansson Learns To Love Monogamy

LOS ANGELES, Calif. -- Scarlett Johansson doesn't believe in monogamy - unless she's involved.

"I don't think it's a natural instinct for human beings," she told Cosmopolitan, recalling comments she made while promoting "Match Point" in 2006. "Monogamy can be hard work for some people. I don't think it applies to everybody, and I don't think a lot of people can do it."

But Johansson, now engaged to Ryan Reynolds, says she is one of those people.

Josh Hartnett To Channel Tom Cruise In West End 'Rain Man'

LONDON, U.K. -- Josh Hartnett will make his professional stage debut, stepping into the shoes of Tom Cruise for the role of Charlie Babbit in "Rain Man," according to the BBC.

Hartnett, 29, will star in the London West End version of the Oscar-winning film when it bows in September.

But which actor will play the role of Charlie's autistic brother, Raymond - a role made famous by Dustin Hoffman in the 1988 film?

Engaged Scarlett Johansson: "I Believe in Finding a Soul Mate"

PLUS: She says she "would never want to be" in an open relationship more »

Hollywood Joins Ledger's Family For Emotional Service

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Casting Call: Winona Ryder Beamed Up To New 'Star Trek'

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