In the 1970's, choreographer Twyla Tharp and Mikhail Baryshnikov collaborated, resulting in a dance that was "totally unexpected" for the classically trained ballet star from Russia. Archival footage shows Baryshnikov in "Push," which starts in a modern "slouch" style and continues with "all he's got." "It can only have happened between the two of us at that moment in time," Tharp recalls.