By all accounts a serious cultural innovator, Pierre Henry revolutionized the concept of "music" (much as John Cage would do in the years to follow) by defying expectations of melody and rhythm, and simply taping extraneous sounds from the world outside of the recording studio that he edited into compositions such as Symphonie pour un homme seul and Messe pour le temps present. As a result, he influenced avant-garde musicians the world over and contemporary DJs as well. With their documentary Pierre Henry: The Art of Sounds, directors Franck Mallet and Eric Darmon follow Henry on one such adventure, as he searches for the "perfect" sound in Paris's Coulée Verte. That footage is then intercut with vintage archival clips of audience members leaving the debut performance of Henry's classic Concert couché, and offering their initial reactions.