Actors didn’t lip-synch beautiful pre-recorded songs in the filming… they sang live each time, and those will be what is used in the final cut. This video shows how the new technique resulted in vivid, dramatic, far more emotional performances.

Back in May when the first movie trailer came out, many noted Anne Hathaway’s noticeably raw (and some even said unpolished) performance of “I Dreamed A Dream.” Knowing the technique used now adds some insight into the emotional nature of the performances. The intent was never to have the often over-audio-engineered veneer of traditional movie musicals.

The film comes out this Christmas.

Below, the behind the scenes clip, and below that, the movie trailer.

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