JACKASS: NUMBER TWO opens with a running-with-the-bulls sequence that sends the movie's stars -- and the animals -- crashing through a suburban set's fake walls and windows. On one hand, the stunt compares the annual Pamplona spectacle and the Jackass spectacle, asking viewers to see the likeness between vaunted cultural traditions and this (debatable) "art" form. It also makes a comparison between the arts of movies and of violent stunts. Rendered in grandiose slow motion, the sequence parodies the way movies are supposed to work: You introduce your stars and the concept, and then you put them through some challenges, leading to education or evolution. In Jackass, everyone knows going in that the stunts are stupid and the effects painful. And so, the stars and the concept themselves become the challenges, and transformation and resolution are about as likely as anyone in the cast escaping without a hit to the crotch. Or so it seems. The trick of Jackass is that it's wholly conventional. For all the seeming outrageousness of the premise -- don't try these stunts at home, expect to be offended, you're watching professionals -- Number Two uses familiar, simple structure. The boys indulge in pain and pleasure, damaging themselves and each other because they can. By the time the finale rolls around -- a song and dance extravaganza complete with high-kicking girls, tuxedo T-shirts, and an homage to Buster Keaton -- viewers feel as exhausted as the players look, and as unsatisfied. The end is never the end. That said, the musical number points directly at the motto of the Jackass crew: This is the time of your life to have fun and do whatever makes you laugh. The lyrics are punctuated by over-the-top stunts in the background, pointing out the obvious and proactively acknowledging the guys' insanity before critics do.