Roger (JON HEDER) is such a mild-mannered NYC meter maid that he often pays for those he tickets to avoid confrontations with them, something that his boss Sergeant Moorehead (LUIZ GUZMAN) and others find amusing. It also means he can't get up the nerve to ask out his pretty neighbor, Amanda (JACINDA BARRETT), whose acerbic roommate Becky (SARAH SILVERMAN) doesn't even try hiding the fact that she doesn't like him.
Based on that and a kid dumping him as his "big brother" sponsor, Roger has a breakdown, thus causing an acquaintance, Ian (DAVID CROSS), to give him the number for a school that can help people like him, stating that he benefited from it. Thus, along with fellow students including Walsh (MATT WALSH), Eli (TODD LOUISO) ad Diego (HORATIO SANZ), Roger ends up in a self-confidence class run by Dr. P (BILLY BOB THORNTON) and his aggressively angry assistant, Lesher (MICHAEL CLARKE DUNCAN).
Demonstrating no sympathy for these "losers," Dr. P and Lesher set out to teach Roger and the others how to be self-assured, not put up with others, and get the girl, all without caring how they're perceived. As Roger progresses through the course, he thinks he's getting the hang of it. That is, until he learns that Dr. P is also putting the moves on Amanda. Hoping to intervene before it's too late, Roger then sets out to defeat his teacher at his own game.