MTV News talked to Burlesque director Steven Antin about the difficulties of pulling off the lavish musical numbers in the film.

The characters surely made it look effortless, however, Antin assures us that a lot of hard work and sacrifice went into the making of the film.

“Each of them had their own set of issues," he explained of the performances.

"Christina's ballad, 'Bound to You,' in its absolute and total simplicity was extremely complicated in terms of lighting and colors and texture. Executing that with the amount of smoke we had in the room and the backlighting, and the way that I wanted her hands and her body to cast shadows over the audience ... it's seemingly staggeringly beautiful, but technically it was really, really difficult to execute and very time-consuming," he said.

He continued on to say that the last number, “Show Me How You Burlesque,” which Christina Aguilera wrote for the film, was difficult because of the time frame it was shot in.

"We were shooting for a long time so that was extremely challenging and difficult to execute, especially in two days,” he said.

"I always ask singers to sing every take; you have to," Antin said of his anti-lip-syncing rule. "For me, I have to because you create a completely different image when you're lip-synching," he explained. "Your whole entire body moves differently, so I would always ask the singers to sing during their takes.

This wasn’t a problem, the first-time director reveals. "What was extraordinary about this, was Cher was doing her solo, 'You Haven't Seen the Last of Me,'" adding, "I could hear her over the playback, perfect pitch. She still has that powerful of a voice and I was just blown away because the playback is so loud. Same with Christina, I could hear her singing over the playback and I was just completely moved and everybody was blown away by it."