It's not surprising that a spotlight vehicle for a singer trying to become a movie star simply demonstrates Jessica Simpson's lack of screen charisma and acting chops. What's odd is that the underdog workplace-comedy wrapped around her is so tossed-off and muddled it'll likely bore even the blue-collar male audience at which it's aimed. Workplace resentment has fueled many funny films and TV shows, from Office Space to "The Office," but here the bad guy is a hard worker who puts in long hours on a menial job, so you gotta ask: What's wrong with this picture?

The ostensible hero, Zack Bradley (scruffy standup comic Dane Cook), is a box boy at a SuperClub discount-warehouse store; since it's unionized, that makes it closer to Costco than Sam's Club. Slacker Zack and his three goldbrick friends-badly nearsighted Lon (Andy Dick), philosophical Iqbal (Brian George) and good ol' boy Russell (Harland Williams)-have a regular card game in their "clubhouse" hidden amid pallets of boxes. They steal petty items like candy bars, which they use to bribe the human-resources lady so that she'll turn over private employee records, and are basically admired for being part of the reason everybody-including the target audience-complains about declining customer service.

Zack has a childish obsession with Vince Downey (Dax Shepard), who's pulled himself up from entry level to head cashier, entertaining the local lovelies with Tom Cruise Cocktail moves, juggling cat food and cornflakes through the scanner and through the air to his personal peon, bagger Jorge (Efren Ramirez, charming in a stock role). Vince is arrogant, but we get mixed signals on whether or not he's creepy: A waitress he'd dated comps him and his current date, new cashier Amy Renfro (Simpson, in consistently ridiculously push-up hooker-wear), when Vince discovers that Zack's pickpocketed his wallet, so how bad can Vince be?

If a hero is only as heroic as his nemesis is bad, then this film has the pettiest hero to come along in ages. It's one thing to regularly deface Vince's Employee of the Month picture; that's just schoolyard stuff. But what life does Vince have? He probably never attended college if he's had to climb up to the grand position of head cashier, and he drives a crummy 1981 Honda with a transmission that sticks. How sad is that? And Zack, our "hero," actually steals the guy's beat-up car for the company to sell. What's Vince's terrible goal that merits punishment by this smug slob? To be Employee of the Month 18 months running and win a Chevy Malibu. Not a sports car. Not some luxury Lexus. A Chevy Malibu. That's the bad guy?

Phil Silvers' classic con man Sergeant Bilko, of '50s TV fame, ran poker games and goofed off as well, but the show made it clear his motor pool ran so well that he and his boys had a lot of down time to fill. And Bilko never attacked the clueless colonel who ran the Army post. That's just one example of a play-the-system comedy done well. Whereas this movie is an example of it gone to hell.