May 10, 2011 - Ian Gavan/Getty Images Europe more pics like this »
4. Rachel McAdams

Whether she's dyeing her hair pink or keeping it natural, Rachel McAdams knows how to make an entrance. At this year's Cannes Film Festival, she wowed on the red carpet in a sensational Marchesa gown. This Canadian's ability to shine places her at the No. 4 spot on our list.