You'll never see Slipknot take the stage unmasked, but they sure as hell rehearse without their getups on! You can check out a brief clip of the band doing exactly that above, which is all part of Slipknot's coming Slipknot: Day Of The Gusano documentary and live film.
Slipknot: Day Of The Gusano is out in theaters come September 6, presumably with a DVD release to follow.
