The 90210 actress - who is the daughter of Bruce Willis - turned heads for all the wrong reasons while stepping out at the 5th Annual ELLE Women in Music Celebration in Los Angeles.
Clearly wanting to make a statement, Rumer sported an all-black outfit complete with a crop top to flaunt her toned midriff, plus a matching skirt with huge cut-outs running down one thigh.
But unfortunately for Rumer, as soon as she turned to the side her saucy ensemble revealed a little more than she bargained for.
Not only did the starlet flash more than a hint of leg, she also gave us all a glimpse of her bright pink knickers.
Oops - what a disaster!
Then again, things could have been much worse. She could have gone commando for the occasion!
Would you dare to wear Rumer's skirt? Let us know by commenting below as the best comment across the site each week wins £50!
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