Ability over Appearance: Malcolm was originally written to be nine years old whereas Frankie Muniz was thirteen when the series first began filming. He even gave his mother a thumbs down as soon as he came out of the audition room. However, the producers were so enthralled by his performance that they decided to age Malcolm up to a middle schooler, and give Muniz the part. When the young actor found out he got it, he jumped on the hotel bed.
Breakup Breakout: While the rest of the cast have yet to work on another project of this size, Bryan Cranston (Hal) would go on to star as Walter White on Breaking Bad, a role that he won four Emmy awards for, three of them consecutively. In fact, at this point, Cranston is better known for his role on Breaking Bad than his role on Malcolm.
The writers started up a game called "What will Bryan Cranston do?" which led to them writing in plots of him doing roller disco and other bizarre and increasingly dangerous stunts just to see if the actor would ever say no. Not only did he not object, he also kept pulling them off. After this culminated in Bryan being covered in live bees in one episode, the name of the game changed to "What won't Bryan Cranston do?"
Erik Per Sullivan actually knows how to play the piano and was able to work it into the series.
Cowboy Be Bop At His Computer: Going against the producers' decision to keep the family without a last name, the episode blurbs on the UK DVD sets refer to the main characters as "the Wilkersons" as if the name was canon.
Frankie Muniz was around 13 when the show started filming, playing an eleven-year-old. Frankie Muniz looks absurdly young for his age (even as an adult), so it's kind of justifiable. However, many of the show's guest stars are less justifiable and more obviously older, such as Patty Henderson the babysitter (27 playing roughly 16), or the 12-year-old date Francis was stuck with, played very obviously by a 16-year-old.
Averted, there is some variation on the exact ages between child actors and their characters but generally its teenagers playing teenagers. Frankie Muniz (Malcolm) is actually a few months older than Justin Berfield (Reese). Not that obvious early in the series (it's likely why he was cast as Reese), but Berfield remained taller than Muniz throughout the series' run.
Played straight in one of the last episodes, where Malcolm organizes an alternative prom with a high school character played by a 26-year-old actress.
Emy Coligado was in her 30s when she started playing 19-year-old Piama.
Directed by Cast Member: Bryan Cranston directed the episodes "Stereo Store", "Vegas", "Dirty Magazine", "Experiment", "Buseys Run Away", "Billboard", and "Malcolm Defends Reese". Christopher Kennedy Masterson directed the episode "Hal Grieves".
Irony as She Is Cast: Two episodes from Season 6 (Hal Sleepwalks and Ida's Dance) depict Malcolm as being musically inept. note The former has him learn the guitar to create a "masterpiece" song, only to end up rewriting the Meow Mix jingle, while the latter had him fail a music appreciation course.In real life, Frankie Muniz is actually a self-taught drummer (having played them since he was 12); he'd go on to play with the indie rock band Kingsfoil in the early 2010s.
Keep Circulating the Tapes: Music rights are the reason why DVDs from Season 2 onward have never been released (except in the UK and Australia). That being said, the full series is available on Hulu (previously streamed on Netflix for a couple years) and the music that would have been removed from a DVD release is there.
Money, Dear Boy: When Bryan Cranston realized that his humming and whistling as Hal was netting him royalty checks as the originator of those melodies, he kept doing it and used the modest money it brought in to buy beer for the show's crew.
No Stunt Double: Bryan Cranston did several of his own stunts. Besides the cartwheel and the headstand, Cranston did his own roller disco skating, spending all the free time he had in the week and a half he had to learn how to skate. After one of the show's writers asked jokingly whether Cranston would be willing to wear a suit of live bees, Cranston said he would, so they wrote a script around the idea ("The Bots and the Bees"). He ended up covered in ten thousand bees, and only got stung once.
Orphaned Reference: Francis wears a name tag labeled "Wilkerson" in the pilot. This was meant to be the family's surname in the early script before they decided to go with No Last Name Given.
Screwed by the Network: Like Futurama, Malcolm had its ratings killed by being placed immediately after National Football League games, subjecting it to constant Sports Preemption when the games would run over their allotted time. It was then moved to the Friday Night Death Slot for Season 7 which dropped ratings further, only for it to be moved back to Sundays at 7:00 PM partway through the season, which again set it up to be constantly preempted by NFL coverage. At least Fox allowed the series finale to air at 8:30PM to ensure all markets would be able to see it.
Separated-at-Birth Casting: It's actually pretty insane how much like a real family almost the entire main cast looks like. The only real standout is Dewey, who has blonde hair that's textured differently from everyone else's.
Star-Making Role: For the entire lead cast, Malcolm remains their best known role — except, of course, for Bryan Cranston, whose best known role by far is now Walter White, although Malcolm is still easily second place for him.
Throw It In!: Jamie was originally supposed to be a girl but Bryan Cranston accidentally said mister instead of young lady.
The fake ATM scam that Francis fell for which got him fired from the Grotto was supposed to be elaborated on. Originally, Eric was meant to return and mastermind the scheme, setting Francis up as the fall guy as revenge for stranding him as they left Alaska, and stealing enough money from Otto to fly back home. The brothers were to beat him up after his plan was revealed.
Lionel Herkabee's karma in "Malcolm Defends Reese" was originally going to feature the return of Principal Block from "Dirty Magazine". In the original script, Block learns from Malcolm that Herkabee did not pass Physical Education, which was a requirement in order to win the award for highest GPA. Shortly after revoking Herkabee's award, Block cusses him out and fires him. Block also gives the award to Malcolm.
In that same script, Malcolm learns from a former gym teacher that Herkabee failed the class his junior year due to poor coordination. Because gym was a requirement for the award, Herkabee skipped the class and created his own AP courses. Due to the gym teacher and Malcolm's shared hatred toward Herkabee, the latter was given a copy of Herkabee's grades in gym to expose him and humiliate him in a public scale.
Caroline Miller, Malcolm's Krelboyne teacher in the first two seasons, was going to become a more mean-spirited character after the events of "High School Play". Had Caroline returned in season 3, she would've gotten revenge on her students for nearly endangering her and her newborn's lives. Not wanting to play a bad character, Catherine Lloyd Burns, who portrayed Ms. Miller on the show, refused to return and was replaced with Lionel Herkabee (Chris Eigeman). Ironically, Herkabee was intended to be a good-natured character who would've reported Miller's behavior to the principal.
Write What You Know: Creator Linwood Boomer based the series on his own experiences growing up as the gifted middle child in a lower-middle-class family of four brothers.
Written-In Infirmity: Jamie was added to due to Lois' actress being pregnant in real life. Lois also went to stay with her sister so Jane Kaczmarek could have maternity leave.
Merrin Dungey, who plays Kitty, played Malcolm's teacher in the pilot.
The loser dinner show host was reused for Chad's father in the episode where Dewey got Chad to have a sleepover with him.
Jennette McCurdy, who played Penelope, one of Dewey's Busey classmates, also played the female Dewey in "If Boys Were Girls".
Rheagan Wallace played a character who married Reese also played a girl who took Drivers Ed. with Reese.
Alessandra Torresani twice plays Malcolm's girlfriend. First as Sara in "Malcolm's Girlfriend" and Kirsten in "Thanksgiving". However, her face was never shown in her first appearance.
Scott Adsit plays two different characters over the show's run. In "Emancipation", he plays the sleazy small-time Alabama lawyer who fast-tracks Francis's emancipation, and in "Health Insurance", he plays a Lucky Aide employee named Joe, who most definitely does nothave a large role in the episode as the union snitch.
James Henriksen has two minor roles, first as the apathetic waiter who delivers Kitty her wrong order in "Dinner Out" and later as one of the guards in "Zoo".
The (twin) actor(s) who ended up playing Jamie in his later appearances originally played a different baby in the episode where Hal attends a Father-child bonding class with Penelope. This is a bit jarring upon re-watch. It's also kind of weird to see an obviously Hispanic baby in an otherwise blonde-haired blue-eyed fam—Wait a minute!
Malcolm premiered in January 2000, just under a year after Family Guy. For just over two years, until Family Guy's initial cancellation in 2002, and again during Malcolm's final season (2005-06), Fox was airing two different half-hour comedies about dysfunctional families with mothers named Lois.
For the record, the anime briefly featured in the opening is Nazca.
