At the end of the movie, when Billy Flynn (Richard Gere) is performing the musical number "Razzle Dazzle", towards the end of the number, he is walking on top of the ledge. He stops and is singing and right behind him you can CLEARLY see a camera, a camera man and other equiptment. They are just standing there while Billy is singing. It is kinda hard to catch, it's easier to see if you can pause it.