Revealing mistake: When Troy says "I'll sing with her," Ms. Darbus turns around "in response" to his voice before he even says anything.
Continuity mistake: When the Spanish singer is singing on in the club for the first time on her own, at the end of her song she stamps on her hat flattening it. In the next shot, the hat is back to normal.
Continuity mistake: In the scene where Effie sings "Curtis, this time Effie's gonna win", Curtis turns his head a little to his left when Effie sings "win" at his face. But at the next shot, camera behind Curtis, Curtis' head is slightly turned to his right. (01:52:35)