If you've never seen A Chorus Line, Every Little Step probably isn't the best introduction. Adam Del Deo and James D. Stern's documentary about the origins of the record-breaking musical and the casting of the 2006 Broadway revival dissects the work, revealing all its secrets.

If you've never seen A Chorus Line, Every Little Step probably isn't the best introduction. Adam Del Deo and James D. Stern's documentary about the origins of the record-breaking musical and the casting of the 2006 Broadway revival dissects the work, revealing all its secrets.

The initiated, however, are in for a remarkable portrait of the show's origins, and the amount of sweat that goes into whittling an open casting call of several thousand down to a few handfuls of dancers.

Stills, archive footage and audio recordings evoke the night in 1974 when Michael Bennett brought together 22 dancers for a 12-hour discussion about their lives, the foundation for A Chorus Line.

The story of how it went from there to success on Broadway is filled in by Marvin Hamlisch and Donna McKechnie, among others, and threaded through that history is the modern-day search for just the right people to take on roles to which the original cast had real-life connections.

Listening to the same song through repeated auditions can get to be a bit much for all but die-hard theater lovers, but this otherwise fascinating peek behind the curtain does a good job of getting the show's originality and timelessness stuck in your head.