Main[ edit ] Lois Jane Kaczmarek: The family's wildly hotheaded and stubborn mother. An intelligent and decisive woman, most of her bullishness comes from her constant battles throughout the series to keep her badly behaved, highly destructive boys in check, while maintaining a menial job at a Lucky Aide drugstore.
Despite her constant aggressiveness, she is motherly  and will defend her family fiercely, especially towards neighbors and others who view them as poor trash; in one episode, she finds that Malcolm and Reese discovered their neighbor having an affair with her Hispanic gardener while they planned to frame her son for theft, but doesn't punish them for their actions as this counted as revenge against the woman, who hated Lois.
Lois is disliked by both Hal's wealthy family and her own parents. She has a younger sister named Susan, who blames Lois for stealing Hal from her. Neighbors despise Lois and her boys and celebrate the weekends when they're gone. In the series finale, she discovered that she and Hal are expecting a sixth child. Hal is a well-meaning, loving, but inept and somewhat immature father, and is completely dependent on Lois, whom he loves absolutely.
He comes from a wealthy family that does not accept Lois as his wife and wishes that he married Susan instead. Because his family is disrespectful towards Lois, he rarely mentions them and avoids his family. Hal loves his boys and will sometimes sneak them out for fun father-son activities behind Lois' back. Hal is an indecisive character who frequently picks up new hobbies for short periods of time, such as speed walking, or painting, and is irresponsible with the money he earns from his low-paying desk job.
His indecisiveness was explored in "Living Will" from a childhood which he had a hard time making decisions for himself and because of this, he always deferred to Lois to make them for him. In the series finale, he discovered that he and Lois are expecting a sixth child. Hal has a high sex drive, this was revealed in the episode "Forbidden Girlfriend" when Lois is taking medication and is unable to have sex for an entire week, it is mentioned again in the episode "Poker 2" when Hal tells his friends he has sex 14 times per week.
Hal's best friend is Abe Kenarban. Hal and Lois' first son. At the beginning of the series, he is attending military school in Alabama ,  run by the strict Commandant Spangler Daniel von Bargen. He has himself legally emancipated at the start of Season 3, leaves the school, and travels to Alaska. Although a juvenile delinquent, he is street-smart. Francis becomes a less frequently seen character after season 5, becoming an occasional recurring character and making only a small handful of appearances in Season 6 and the final Season 7.
He admits he likes his job to Hal, but also enjoys frustrating Lois by telling her that he's unemployed. Hal and Lois' second son. Reese is the most impulsive and physical of the boys. Reese is better than Malcolm at devising plans, and is masterful at the rare things which can pin his drifting focus, such as driving, or when he's revealed to be a culinary prodigy , excelling at cooking and baking.
Dewey Erik Per Sullivan: Hal and Lois' fourth son. He is the youngest child until the birth of Jamie, and often falls victim to his brothers' pranks. He plays the piano. Despite his intelligence, he is placed in a remedial class for slower students or " Buseys " due to a misunderstanding. By the seventh and final season of the show, the Busey class is no longer mentioned.
He is the only sibling that eventually breaks the cycle of abusing the younger sibling, which ends up with him acting like a normal, lovable brother towards Jamie. In the series finale, he along with Jamie are seen hiding in the closet after a prank. Catherine Lloyd Burns as Caroline Miller seasons Malcolm's "overly earnest" teacher. She ardently adores Malcolm due to his intelligence. Francis uses her adoration to pay a medical bill to stitch up Malcolm in one episode.
After she gives birth, Caroline leaves teaching. She was also the only non-family member to be credited as part of the main cast in the intro. Malcolm is a genius with an IQ of and a photographic memory.
As the title suggests, Malcolm is initially the middle child of the three living at home; chronologically, he is Hal and Lois' third son. His best friend is Stevie Kenarban. In the series finale, he graduates from high school and starts attending a prestigious college by both scholarship and working various jobs, specifically as a janitor at Harvard University. Jamie James and Lukas Rodriguez season 4 recurring; seasons Hal and Lois' fifth son, born at the end of Season 4.
He is shown to being the only child who is capable of defeating Lois. In the series finale, he along with Dewey were seen hiding in the closet after a prank. Other characters[ edit ] Craig Lamar Traylor as Stevie Kenarban, Malcolm's best friend since childhood who's in the Krelboyne class and is in a wheelchair. Stevie has difficulty breathing and is revealed in season 5 to have only one lung.
He is socially awkward and has trouble making friends. He is very geeky and self-absorbed and in the rare event he is given actual powers, he can also be as bossy as Lois, albeit much less competent than her. Craig also has a non-existent relationship with his estranged father, who is utterly obsessed with running his gym.
Emy Coligado as Piama Tananahaakna, Francis' wife. She is an Alaska Native. She is a good wife to Francis and helps him resolve troublesome situations. Piama has the same type of fiery, unyielding personality as Francis' mother, Lois, who initially dislikes Piama until a disastrous family reunion made her realize how unfair she was to Piama.
It is his call which brings Francis to Alaska. However, Eric is left to hitchhike back home possibly as revenge for suggesting that he and Francis find work in Alaska. Kenneth Mars as Otto Mannkusser, Francis' boss who owns the ranch he works at after he leaves Alaska. Francis tries to protect Otto from being scammed by con-artists and helped him reconcile with his estranged son, Rutger. He is married to Gretchen. Isaac all play Krelboynes from Malcolm's class.
He is missing his right eye, his left hand, and his ring finger on his right hand, and he actually never served war time. He despises Francis because he fought against him. In the end, he loses his other hand to Francis' waving a saber about and later is fired from Marlin Academy. After arriving in Alaska, Francis gets Spangler a job at a retirement home, which gives him free rein to bully the elderly. She despises Francis and Lois, except on one occasion when she was kind to Lois.
Ida has one common interest with Francis: She is generally disliked by the family, bar Reese whom she clearly favors. She lost her leg saving Dewey from being hit by a truck, one of her few recorded good deeds.
She once tried to sue Lois, her own daughter, for slipping on a leaf in the walkway of Lois' house and becoming temporarily injured. She was foiled by Francis and the boys who gave their support their parents and the lawyer willingly abandons her.
Ida favors Susan over Lois as she is more graceful and talented. Meagen Fay as Gretchen Mannkusser, Otto's wife who helps out at the ranch.
Karim Prince as Cadet Stanley, Marlin Academy student, Francis' best friend and informal bodyguard during the show's first season.
Chris Eigeman as Lionel Herkabe, the second teacher of the Krelboyne class and a former Krelboyne himself. Despite sharing many of the same personality traits, he and Malcolm hate each other, but on one occasion Herkabe was nice to Malcolm. He is also bossy, stubborn and sadistic. Herkabe loses his GPA award in light of his actions for flunking Gym.
Brenda Wehle as Lavernia, Francis' first boss, a malevolent woman. Merrin Dungey played two different, unrelated characters. In the pilot episode Dungey plays Malcolm's teacher before he transfers to the Krelboyne class. Later in the first season, she appears as Kitty Kenarban, Stevie's mother who left him and Abe, but then returned. It is shown that Kitty is very overprotective of Stevie.
Her dad is played by Fred Sanders. Hayden Panettiere as Jessica, a girl hired to babysit Reese, Malcolm, and Dewey who later ends up living on their couch temporarily after her dad is arrested.
Jessica is shown to be a very manipulative girl, once showing Malcolm how to emotionally manipulate Lois. She had been known to play tricks on Reese and Malcolm.
Despite this, Jessica has a crush on Malcolm and has shown that she can be a loyal friend. Landry Allbright as Julie Houlerman, a girl whom Malcolm had a crush on Julie Hagerty as Polly, Jamie's babysitter, who is extravagantly open about her personal problems and medical conditions.
In one episode its revealed she has a sadistic, and somewhat threatening, ex-boyfriend named Danny, who only appears once in the show. They end up reconciling and getting back together. Steve Vinovich as Mr. Hodges, the school principal season 7.