Trust Dave. The raunchy slapstick comedy "Saving Silverman" is poorly constructed. For every joke that works there are three that fail. But I laughed out loud a lot during this tasteless farce, thanks to the inspired goofiness of the amazing Jack Black, along with Steve Zahn, Amanda Peet and, in a truly surprising performance, R. Lee Ermey. It's easy to picture the Three Stooges looking down from Comedy Heaven, whacking each other with ball peen hammers while saying with pride, "Ah, our legacy lives on."

The story revolves around three lovable dumb guys who have been best friends since childhood. Wayne (Zahn, the funniest actor in "Happy, Texas," "That Thing You Do" and numerous other comedies) earns his living in the varmint control field, driving a truck that reads, "Cowboy Wayne: Pest Posse and Rodent Wrangler." J.D. (Black, the chief record store god in "High Fidelity" and one half of the satiric cult rock duo, Tenacious D) is a dedicated Subway employee best known for attending the high school prom with a tuxedo painted on his naked body. Along with their buddy Darren Silverman (Jason Biggs, the pastry aficionado from "American Pie") they channel their fanatical appreciation of Neil Diamond by performing in the tribute band, "Diamonds in the Rough."

All is well until one night at a local bar, when J.D. and Wayne decide to help their pal overcome his depression. Darren has the blues because he never mustered the nerve to ask out Sandy (Amanda Detmer), the high school cheerleader of his dreams. Their solution is to maneuver him to the table of a beautiful woman who appears to be out of his league.

Big mistake. Judith (Amanda Peet, scene-stealer from "The Whole Nine Yards") is pure evil, a manipulative psychologist who makes Darren her love slave. "He's my puppet," she says with authority. "And I'm his puppet master." After one disastrous visit with the boys ("A beer bong for m'lady?" offers J.D., the perfect host), she orders Darren to quit the band and stay away from his friends. In short order, she announces their engagement.

Horrified beyond belief, J.D. and Wayne decide they must save their brainwashed friend. The plan they cook up is, in their eyes, simple and logical: Kidnap Judith, fake her death and fix Darren up with Sandy, who is about to become a nun. But Judith is no meek captive. Dipping into her arsenal of mind games, she works wicked psychobabble hoodoo on her jailers.

Not enough plot for you? How about this: The boys must also deal with their mentor ("Stay away from women. All they want is your man juice!") and former football coach (Ermey), fresh from prison and eager to help, although most of his solutions involve murder.

This all may read as generally hateful, and misogynistic in particular, until you compare it to any Three Stooges film. Most of the slapstick plotlines pitted Moe, Larry and Curly against either bosses or women. "Saving Silverman" plays in the same sandbox – with a lot more crude sexual subtext, of course.

Unlike "There's Something About Mary," which was consistently hilarious, "Saving Silverman" is a hit and miss affair. Director Dennis Dugan ("Big Daddy") is a gentle, nice man, but he does not know how to stage a scene for maximum comic effect. An uneven script that makes some fundamental mistakes further hampers him. Jason Biggs' character is overly bland; he doesn't fit with J.D. and Wayne. Gags set at Sandy's nunnery don't deliver and an appearance from the real Neil Diamond fails to pack the comic punch it should.

Thank goodness for the rest of the cast. Sharp and focused, Amanda Peet makes a great villain and the most dangerous kidnap victim since Bette Midler in "Ruthless People." Steve Zahn is a wonderful cartoon, displaying perfect timing and wisely underplaying some of the film's most outrageous moments. As always, Jack Black works his pudgy, manic magic, letting Zahn dominate most of the shtick while providing riotous backup. But the big surprise is R. Lee Ermey, best known as the ferocious drill sergeant in "Full Metal Jacket." Playing wildly against type, he gives an incredible no-holds-barred performance and handily steals every scene he is in, an even more remarkable feat when you consider that he shares most of his screen time with Zahn and Black.

Bottom line: "Saving Silverman" is an awkward, spotty, poorly staged dumb guy comedy that still made me laugh a lot. Jack Black did something to make it worth watching, as did Steve Zahn, Amanda Peet and R. Lee Ermey.