The story's protagonist, Peter LaFleur (Vince Vaughn), is a charismatic underachiever and proprietor of a rundown gym called Average Joe's. The facility's clientele of decidedly less-than-"average Joes" is made up of a self-styled pirate, a scrawny nerd who dreams of impressing an unattainable cheerleader, an obsessive aficionado of obscure sports, a dim-witted young man, and a cocky know-it-all who, of course, really knows nothing.
Peter's humble gym catches the eye of White Goodman (Ben Stiller), the power-mullet-sporting, Fu-Manchu-d, egomaniacal owner of Globo Gym, a gleaming monolith of fitness. White intends to take over Average Joe's, and Peter's non-existent bookkeeping is making it all too easy for him. A foreclosing bank has stationed attorney Kate Veatch (Christine Taylor) inside Average Joe's to finalize Globo's takeover of the gym. But Peter's boyish charms win her over and Kate joins his team of social rejects to beat the odds - and their own ineptitude - to try to save Average Joe's. How? A showdown dodgeball competition against Globo Gym.
Set in a future Earth (2035 A.D.) where robots are common assistants and workers for their human owners, this is the story of "robotophobic" Chicago Police Detective John Spooner's (Smith) investigation into the murder of Dr. Alfred Lanning (James Cromwell), who works at U.S. Robotics, in which a robot, Sonny (Tudyk), appears to be implicated, even though that would mean the robot had violated the Three Laws of Robotics, which is apparently impossible. It seems impossible because.. if robots can break those laws, there's nothing to stop them from taking over the world, as humans have grown to become completely dependent upon their robots. Or maybe... they already have? Aiding Spooner in his investigation is a psychologist, Dr. Susan Calvin (Moynahan), who specializes in the psyches of robots.