jackass is a popular show on MTV in which amateur stuntman (and Donny Osmond lookalike) Johnny Knoxville and his lunatic friends come up with endless ways in which to maim, humiliate, or sicken themselves and each other. No plot, no story, just a series of pranks, one after the other.
jackass: the movie is 87 minutes of same, featuring some stunts too extreme to show on television (usually because of male nudity). So you get guys eating snow soaked with their own urine, letting baby alligators bite them on the nipple, defecating in uninstalled toilets in the middle of hardware stores, shooting roman candles out of their butts, and vomiting frequently.
Walking out of the theater, most of the guys I saw were smiling and shaking their heads, their female dates generally annoyed and disgusted. You get the picture.
As for me? Not having seen the show, I still found the film watchable in a highway accident kind of way, impressed less by the grossout humor than by the bizarre creativity of the stunts ("Off-road Tattoo", anyone?) and the jovial masochism of Knoxville and his buddies. Call them stupid, call them insane, but there's no doubt that they are having the time of their lives, and there is something infectious about that.