Continuity mistake: In the scene when Lulu Bains is prancing around in the dressing room, there is one steady shot of her. In this shot, as she moves around, the right strap on her outfit begins to slip off her shoulder. The shot ends by her side with the strap completely down her mid-bicep; however, in the very next shot, which is from the front, her right strap is back up, and it's her left strap which is halfway down. The print wasn't reversed to this effect, either.
Continuity mistake: At the end, there is a scene in a burning church. A lady runs by Elmer in a blue jacket, and her jacket is on fire. Elmer pulls the burning jacket off her, and beats out the flames. If you follow closely, you see Elmer grab the lady's shoulders, then you see Elmer holding a blue jacket in flames, while the lady is still standing behind him with a blue jacket on. This second blue jacket disappears, and the lady runs off with no jacket. (02:20:10)