A sexy Kate Beckinsale wore a silver Dior crystal gown at the "2010 amfAR's Cinema Against AIDS" gala held near Cannes on Thursday. We know the draped, jeweled part of the dress is supposed to be the focal point, but we can't our eyes off her shapely backside.

The actress is set to star in "Underworld 4." Co-starring Michael Sheen and Bill Nighy, the fourth installment of the popular franchise is scheduled to be ready for theaters in 2011.

Her most recent films include "Whiteout" and "Everybody's Fine."

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