Malcolm, whose frenetic home life is a kind of zoo, begins the fourth season by accompanying his family to the real thing. A visit to the zoo offers...

High school's first day vexes Malcolm, who acquires an unfortunate nickname; and Hal, a parental "volunteer" running afoul of authority.

Christopher Lloyd adds to his gallery of eccentric characters, playing Hal's quirky, cranky and very wealthy father, Walter, in this rollicking...

Acting dumb like Reese eases Malcolm's stress and lands him a date with the new light of his life, an attractive girl who's really a dim bulb.

Brotherly love is lost on Malcolm and Reese, now out to sabotage his sibling's birthday in devilish strikes met with crafty counterattacks.

Malcolm starts to date Nikki. Meanwhile, Hal and Lois must take abstinence pills in an attempt to be better parents. At the ranch, Otto is furious...

After joining the basketball team at school, Malcolm soon finds himself under the coach's skin due to his constant complaining, which eventually gets...

On a visit to Francis' dude ranch Hal can't help being disappointed in Francis' success, Reese and Malcolm fear Francis has turned into an overly...

Grandma Ida is even nastier than usual (if that's possible) because of a tumble down the front steps that resulted in a broken collarbone, prompting...

After being rattled by a battle among the boys, a pregnant Lois ponders the consequences of raising another brawling kid. So she fantasizes that her...

A sex lecture from Lois rattles Malcolm; a ranch calamity unnerves Francis; disharmony among Hal's music group is a prelude to their concert. Also, a...

After Lois is out of town, Malcolm and Hal got into a fight leading Malcolm to get expelled from his house. Malcolm lives with his girlfriend in her...

Jessica, a sly, 16-year-old sitter outfoxes the boys while Lois is away and Hal's busy with a second job as a whiz of a salesman.

Malcolm tries to emancipate Dabney from his overbearing mother while Hal invites his ne'er-do-well old buddy to the house. At the ranch, Francis is...

A garage sale that's entrusted to Reese (yikes!) yields treasures near and dear, like Hal's old radio transmitter, which he makes operational. And a...

An academic competition faces the Krelboynes in an event Malcolm derides. Especially when he learns his teacher has a cheating plan. Also: a...

Hal and Lois are penning their will, and think back to all the trouble their sons put them through. It is there that Lois' problems with Francis are...

When Hal and Lois go out of town for a "last chance" getaway before the baby comes, Reese has a big bash that gets out of hand. College-age thugs...

Leonard, a cynical, genius chess player with no friends or job, makes Malcolm think he could grow into a similar adulthood. Determined to prevent...

Lois goes into labor while Hal and the boys are at a bridal exposition. Ida moves in after her apartment burns down and she refuses to stay with...

While Lois is in labor, the house is hectic, and Hal, desperate to get home, has crashed the car on the way out of the expo.

With the arrival of their fifth child, Lois and Hal search for a "creative" daycare solution.