The family travels to Las Vegas when Hal experiences a dream about hitting the jackpot; Dewey and Reese enter an enormously obese rabbit in a contest; Lois gets to meet her favorite singer backstage; Otto and Francis get trapped in a well.

Lois gets Malcolm a job at the store, exposing Lois's well-kept secret; Hal and some other fathers start betting on babies; and sick of the way his brothers treat him, Dewey travels to the farm to visit Francis.

Hal and the boys enter the season of goodwill in a competitive spirit when the local church starts to undercut them on Christmas tree prices.

Lois and Hal clash after Hal purchases a hot tub; Malcolm gets his driver's permit, only to get mixed up in a dispute between Polly and her ex-boyfriend; and Reese steals Dewey's friend.

Malcolm volunteers for the company's softball team, only to realize that Lois is the coach; Francis sets out to prove he's not lazy; and Hal interviews for a job at a company that might be recruiting secret agents.

Lois has a dispute with Hal and the boys' favorite restaurant; Malcolm clicks with his girlfriend's family to the point where he forgets about his girlfriend; and Francis gets an assistant who tends to his every whim.

Reese is kicked out of the house and soon discovers how expensive renting an apartment is. Meanwhile, Malcolm helps a football player apply to college.

Polly begins dating Abe and Craig; Malcolm refuses to believe in the power of Dewey's lucky shirt; the ranch hands make fun of Francis; and Lois takes the kids to a baseball convention.

When Dewey is in danger of joining the Krelboynes, Malcolm interferes with disastrous results. Meanwhile Hal 'discovers' his latest mania when he sees Craig dancing in a family restaurant.

Reese inadvertently perfects Malcolm and Stevie's science experiment, but can't remember how he did it; Dewey dreams up reasons for people to buy the candy he's selling door-to-door; and Francis aids a piglet.

When Reese's girlfriend Beth cheats on him with Malcolm, he runs away to join the army; Meanwhile, Hal is arrested for supposedly hatching out an entire criminal scheme at his job.

Hal's trial continues as the evidence pointing against him grows; Meanwhile, at training camp, Reese and his team are captured by enemies because of Reese.