A gifted young teen tries to survive life with his dimwitted, dysfunctional family.
Malcolm finds his life as the middle brother in an eccentric family made even more difficult by his being placed in a class for gifted students at school where he reluctantly befriends another boy with a high IQ and stands up to a bully.
Lois must take drastic steps to discover which of her sons ruined the special dress she bought for an anniversary dinner with Hal.
Lois and Hal leave the boys alone for the weekend with Francis. the boys assume that if all goes well, Francis may not have to go back to military school.
Parallel stories pit Malcolm against a bullying, obnoxious new kid and Francis vies with his intimidating, military-school commandant, who's presenting sex-education lectures. Meanwhile, Hal takes heat after cutting down a tree.
Malcolm's cushy babysitting job provides relief from the trailer the family's using while their house is being fumigated, until Malcolm learns that the trust placed in him in his new position is strictly limited. Meanwhile, the military school's master key leads Francis to a corpse, for which he provides a proper send-off.
Malcolm sleeps over at Stevie's house and, appalled at his over-protected lifestyle, persuades him to sneak out to a strange, late-night escapade. Francis deals with hazing at military school. Reese tries to prove he's man enough to watch a scary movie.
