The Cannes International Film Festival is the epitome of elegance, sophistication and Old Hollywood glamour. Grand gowns routinely reign supreme and embellishments are practically a prerequisite. Remember, this is the same festival that tried to ban flats and selfies in 2015. But that doesn’t mean stars don’t try to push the fashion envelope while attending the festival. In fact, Cannes has a rather sordid history of risqué looks (by its standards, anyway), from Madonna shocking fellow attendees in a cone bra back in the early 90s to last year’s gathering where sheer accents were all the rage. And then you have your consummate risk-takers like Anja Rubik, who dare to challenge the festival’s boundaries year after year. For the most revealing looks from the iconic festival, simply click through the slideshow above and learn what not to wear if you ever score an invite to a premiere or a party over in Cannes.