MARITAL STATUS: Single mother to an 11-year-old son, Sebastian
RESIDENCE: New York City
BIG BREAK: Playing Russell Crowe's love, Lucilla, sister of the Roman emperor Commodus, in last year's Gladiator
TYPECASTING: "She looks royal," says Gladiator makeup artist Melissa Lackersteen. "It's the long neck and elegant jawline and very good cheekbones."
HER BEAUTY MANTRA: "I don't like to look too perfect, too done," says Nielsen, "so if I do the mouth, I don't do the eyes. And if I do the eyes, I don't do the mouth."
LESSONS LEARNED THE HARD WAY: The Copenhagen native has taken care to protect her fair complexion from the sun ever since a sailing excursion off the African coast in her 20s left her so burned, she says, "I had to lie covered in zinc from head to toe for a full day. There were cockroaches all over my hotel room. I was scared to death."
THANKS A LOT, BRO: "She was definitely not the prom queen," says Nielsen's brother Ulrich, 31. "She was plain, she wore glasses. There was nothing spectacular about her. The years have been very good to her."