The first thirty minutes of Gaspar Noé's "Irreversible" had a background noise added which hovers around the 28 hz frequency. This type of frequency causes nausea, sickness and vertigo in humans; this might help explain the numerous walkouts on the festival circuit the year the film came out (2002; San Sebastian, Cannes)--though there were other reasons (fire extinguisher, anyone?). "Irreversible," which stars Vincent Cassel and Monica Bellucci caused debate, disagreements and managed at the same time to bring us deep into the moist recesses of France's libidinous culture (swapping and the like).