The Oops: Navigating the tricky , the French actress pulled her skirt apart to aid her movement, inadvertently giving the crowd an eyeful.
Of course, Courtney was loving all the attention and clearly didn't care about her apparent fashion faux pas.
The album has been a labour of love over several years, and sees her perform her favourite tracks from the West End stage, as well as a duet with Sheridan Smith.
From accidental nip-slips, to seriously see-through clothes, click through the gallery to take a look at the most embarrassing celebrity wardrobe fails through the years.
Why are people fighting to free the nipple? He pretended that it was all part of the act.
Some celebs are so lucky that even a wardrobe malfunction can only make them look better, however some of the others are not so lucky.
During her pregnancy with Miles, the Lip Sync Battle host shared an aerial picture of her cleavage, showing one breast noticeably bigger than the other—the consequence of nursing daughter Luna predominantly from one side.
Hadid has undeniably been the queen of wardrobe mishaps so far this year, with three major moments to date -- and counting! This being the unfortunate result: Source: Channel 9 Whoops.