Main •
Bryan Cranston as Hal, the family's well-meaning and loving but inept and immature patriarch who depends on Lois. •
Justin Berfield as Reese, Hal and Lois's second and most impulsive child, who lacks basic life skills but excels at cooking, became a high school janitor at the end of the original series, and now makes money by posting videos of Hal's humiliation. •
Christopher Masterson as Francis, Hal and Lois's oldest and most rebellious child, who was sent to military school at age 15 for bad behavior, but left the school and emancipated himself at 17, and worked several odd jobs nationwide before getting a stable job at a large tech company. He is staying in his parents' garage with his wife while in town for their anniversary. • Keeley Karsten as Leah, Malcolm's daughter, who narrates the series by breaking the
fourth wall like her father does. •
Vaughan Murrae as Kelly, Hal and Lois's self-sufficient, studious,
non-binary youngest child serving as the family's informant, with whom Lois became pregnant in the original
series finale. •
Kiana Madeira as Tristan, Malcolm's girlfriend. •
Jane Kaczmarek as Lois, the family's temperamental and overbearing but intelligent and decisive matriarch, who formerly worked at the Lucky Aide retail drugstore. •
Frankie Muniz as Malcolm, the third child and middle son of Hal and Lois with a genius IQ of 165, who narrates the series by breaking the fourth wall. An alumnus of
Harvard College, which he began attending in the original series finale, he now owns a food charity and has a daughter.
Recurring •
Gary Anthony Williams as Abe Kenarban, Hal and Lois's friend and Stevie's father •
David Anthony Higgins as Craig Feldspar, a close family friend and ex- manager of the Lucky Aide retail drugstore, who now works at Huge Mart •
Emy Coligado as Piama, Francis's
Alaskan Native wife, whom he married while living in Alaska, and is pregnant with their first child • Caleb Ellsworth-Clark as Dewey, Hal and Lois's often-ignored fourth child who is now a successful world-traveling musician. He only appears via web video communication and flashbacks. Dewey was originally potrayed by
Erik Per Sullivan in the original series. • Craig Lamar Traylor as Stevie Kenarban, Malcolm's disabled childhood friend who was born with only one lung and uses a wheelchair • Anthony Timpano as Jamie, Hal and Lois's fifth child and youngest son who was a toddler on the original show and now serves in the
United States Coast Guard Guest •
Dan Martin, Alex Morris,
John Marshall Jones, and Jonathan Craig Williams, respectively, as Malik, Trey, Brian, and Steve, Hal and Abe's poker buddies and fellow stage bandmates. Brian was originally potrayed by Edward James Gage in the original series. • Todd Giebenhain as Richie, Francis's old friend • Erik Gow as Glenn, Stevie's partner, with whom he adopted a son named Max •
Merrin Dungey as Kitty Kenarban, Stevie's mother and Abe's ex-wife •
Eric Nenninger as Eric Hanson, a former cadet at Marlin Academy, the military school where Francis was sent, who moved to Alaska and incentivized Francis to join him. He is still close friends with former cadets Drew Horton and Ken Finley, and they continue to waste their lives pulling pranks, much to Francis's confusion. •
Drew Powell as Drew Horton, a former cadet at Marlin Academy •
Arjay Smith as Ken Finley, a former cadet at Marlin Academy •
Meagen Fay as Gretchen Mannkuser, Francis's former boss at The Grotto and widow of Otto, who himself was killed by a puma. She now works as a doula and is first to discover that Piama is pregnant. •
Finn Wolfhard as Wayne, the event planner for Hal and Lois's anniversary party •
Aryan Simhadri as
Manjushri, a
bodhisattva whose presence Hal hallucinates while on heavy drugs •
Kyle Sullivan as Dabney, Malcolm's former classmate and fellow "Krelboyne", the name given to students in the gifted class • Victor Z. Isaac as Kevin, Malcolm's former classmate and fellow "Krelboyne" • Evan Matthew Cohen as Lloyd, Malcolm's former classmate and fellow "Krelboyne" •
Jett Klyne as Jason, a boy who Leah has a crush on ==Episodes==