When Louis Lumière invented the first portable motion picture camera in 1895, it is safe to say he never envisioned it would be used 115 years later for the purposes of the sort of base, stomach-churning, and just plain idiotic gags found in "Jackass 3D." An unlikely film trilogy based on the now decade-old MTV series, the "Jackass" franchise has become passé and not nearly as shocking as it once was. This is its nadir. As brain cells shrivel in response to the irredeemable, cynical, subjectively worthless experience, the only thing to do is pray for the sweet relief that shall arrive when it is all over.

As skit-laden feature-length films, 2002's "Jackass: The Movie" and 2006's "Jackass: Number Two" were almost equal parts amusing, sickening and flat, cinematic junk food of the "turn-your-brain-off-at-the-door" variety. Thoroughly uninspired and not even trying to one-up its predecessors, "Jackass 3D" just comes off as kind of sad. Closing in on forty, the regular ensemble of perverse stuntmen and pranksters, headed as usual by Johnny Knoxville (2005's "The Ringer"), are getting awfully long in the tooth for this sort of juvenile foolishness..As for the added dimension, it is utterly pointless, rarely used to any noteworthy degree. The title, too, will come off as just plain lame in 2D theaters and once available at home. Complete with an introduction from Beavis and Butthead explaining to audiences the 3D format and instructing them to put their glasses on, the film is nothing but a cheap, awkwardly out of touch money-grab, destined to become dated the second it blessedly exits multiplexes. It won't be a moment too soon.

For those who have managed to overlook all previous "Jackass" incarnations, a bunch of emotionally stunted adults headed up by Knoxville play un-PC jokes on unsuspecting people and perform dangerous and/or painful stunts. There's no plot or thematic relevance, other than its unspoken evidence that these guys are as crazy as craphouse rats and have so little going on in their careers that they feel the need to return once more to the dried-up well where they made names for themselves ten years ago. Almost none of it is funny this time around, hurt by boring and unoriginal shenanigans, poor editing, and a sneaking sense of desperation on the cast's parts.

Whether they're boogie-boarding into an inflatable swimming pool, hitting each other with fish, bats and a giant swinging hand, or gluing themselves to each other and ripping their body hair off, one watching them fast gets the sensation that he or she has seen all this before. Resident director Jeff Tremaine has apparently run out of ideas, each successive asinine scene merely a variation on the last one. In the gross-out department, viewers can look forward to a violent tooth extraction, a butt exploding feces into the air, a slow-motion shot of a filthy port-a-potty being shaken and overturned with an unfortunate soul inside, and the drinking of a cup of someone else's sweat. Cue the rest of the cast (and camera operator) puking all over themselves at the repulsive bodily fluids being obsessively tossed about.

The previous two installments were hit-and-miss, certainly, but there was a certain underlying charm to them even as they worked one's gag reflexes into overdrive. "Jackass 3D" doesn't even have that kind of appeal. There is nothing clever or likable about the stunts, each one akin to grasping for straws in the Arctic Circle. Two of the precious few pranks that do work are the only funny moments—one involving a barroom brawl of little people and the other having to do with Spike Jonze dressed as an old man and making out with his young "granddaughter" in front of shocked passersby—and wouldn't you know it, they're the tamest set-pieces in the whole film. The rest is rotten, slapdash and desperate. An interminable waste of time, money and one's attention, "Jackass 3D" is one of the most joyless film experiences of the year.