Don't sit there and wait for Paul Giamatti to transform Big Fat Liar into something sublime. Although it has some moments, Shawn Levy's film is simply a PG-rated revenge fantasy for the Nickelodeon set. Giamatti plays a similar sort of villain to "Pig Vomit" in Private Parts, which would not itself be a bad thing, since that was a real breakthrough for the versatile character actor. But in Levy's hands, he's so one-dimensionally malevolent that he becomes totally frustrating. And not just frustrating the way villains are supposed to be frustrating -- frustrating because he openly insults numerous underlings with exaggerated vitriol, even in situations when it's clearly in his interest to suck up to them. As a sneakier, subtler character, he would have been more effective. Then again, as one of the revenge pranks involves Giamatti's Marty Wolf getting dyed blue, subtlety is not Big Fat Liar's strong suit. Amanda Bynes does demonstrate the comedic range that has prompted some critics to label her a teen Tracey Ullman, but Frankie Muniz offers up nothing more than his usual brand of brainy precociousness. His character recruits a conspiracy of fellow vengeance-minded individuals, and they concoct the kind of complicated comeuppance that even a seasoned action choreographer couldn't dream up. Hey, never underestimate the cleverness of a kid who doesn't turn in his homework, especially given free reign of a prop warehouse with all the equipment left plugged in.