Johansson, 26, and Penn, 50, began their romance in early January while she was staying at the famous Chateau Marmont in L.A. while filming We Bought a Zoo, co-starring Matt Damon.
"Their first hook-up was in Scarlett's bungalow," a source tells Us Magazine. "Scarlett first reached out to Sean when she was planning to visit Haiti with Oxfam. She knew Sean was living there in a tent and turned to him for advice."
They report that even though Johansson didn't go on the trip, she started having feelings for him. Penn, who recently starred in Milk, split from wife Robin Wright after 14 years of marriage last August.
"Scarlett's smitten with him," the source revealed.
What do you think of Scar Jo and Sean Penn dating? I can totally see her with an older man -- but is he the right one for her? Do you think he is too old for her?
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