Movie stars "stayin' alive"

 
Video link. 

A mashup of the Bee Gee's Stayin' Alive with classic cinema dance segments featuring Rita Hayworth.  It's well done, though a bit long, requiring a looping of the melody.  I presume during film editing the film speed can be tweaked faster or slower to match the music?  Or does this just reflect selection of compatible scenes?

Via Neatorama.