It's still summer-vacation time on the jaunty third-season opener, which finds Malcolm and his rowdy clan cruising on a lake in a houseboat with Stevie and his straitlaced parents, Abe and Kitty Kenarban. Some vacation. The vessel itself is a fright, a weathered heap that Dewey hates from the get-go because "There's no TV! There's no TV! There's no TV!" An equally distraught Malcolm is shanghaied by Hal for a fishing expedition, leaving lucky Reese the chance to trawl for bikini-clad beauties at a nearby camp. Back on board, the close quarters are slowly driving Abe off the deep end.
Malcolm is a regular high school kid trying to navigate his way through life despite the various obstacles thrown in his way a complete misunderstanding of girls, the constant burden of masterminding plans to get himself and his brothers into or out of trouble, and a miserable job at the Lucky Aide not to mention a severe case of teen angst.
Although Malcolm has a genius IQ, he can't seem to make sense of the opposite sex, much less his embarrassing family. Lois is the outspoken, opinionated mom, who still manages to rule the roost even though her boys are growing wise to her crafty ways. Hal, a dad who is just a bumbling, big kid at heart, often finds himself creating more chaos than his five boys combined.