At amfAR’s 20th Annual Cinema Against AIDS Gala held in France yesterday evening, the plucky actress braved what had been a week of tempestuous weather and wore a black Vionnet gown from the fall 2013 collection featuring two thigh-high slits. (And we all know what can happen when a mere breeze hits those). Her dress also had boxy shoulders and a large belt fit for a wrestler. But Dawson had fun on the red carpet. She paired her black gown with white pumps and posed throughout the night, usually displaying one whole thigh at a time, and at times even seemed to be channeling Rihanna.