If your upcoming event has a dress code, you’d better not invite Demi Moore. The actress recently showed that she’s above those sorts of restrictions when she decided to change into blue jeans at a royal ball. (Wait, royal balls still exist?)

Moore attended the costume gala for Princess Beatrice’s 18th birthday with her husband, Ashton Kutcher. The daughter of the Duke and Dutchess of York’s birthday party made the lavish affairs depicted on MTV’s “My Super Sweet 16� look low rent. Her three hundred guest party cost a jaw-dropping $725,000 and took place at Windsor Castle. Those lucky enough to get an invite were told to wear period costumes from 1888 - 100 years before Beatrice’s birth.

Most people, if asked to attend such a soiree, would stick to the rules, but Demi decided to do things her own way. Though she did originally come to the ball wearing a white gown, an insider told the London Mirror, “She went upstairs to change, then she came back a few minutes later in a black T-shirt, jeans and black pumps.� Apparently Demi didn’t think she could get her grove on in the gown. Said a party-goer, “No one else saw fit to change their outfits, and most people who saw Demi before and after thought it showed a thorough lack of respect to the hosts. You wouldn't even wear jeans to go to a decent nightclub - let alone a royal residence.�