Slipknot: Day Of The Gusano is a documentary and live film that will chronicle Slipknot's most recent Knotfest Mexico festival, and will go both behind the scenes and live on stage with the band. You can check out a portion of the band's performance of "The Devil In I" below, as well as see the band rehearse unmasked here.
Slipknot: Day Of The Gusano is out in theaters come September 6, presumably with a DVD release to follow.
