 Metallica are performing their song "Sad but true" in the film. It  was recorded at a regular live show in Salt Lake City on November  22, 2004. The show was interrupted during "Sad but True" but the  song was only played once. To celebrate the premier of the movie at  the Sundance Film Festival on Wednesday, January 25, 2006, the band  played at a private party following the screening that day.