The series follows a family of six (later seven), and stars Frankie Muniz in the lead role of Malcolm, a more-or-less normal boy who tests at genius level; he enjoys being smart but despises having to take classes for gifted children, who are mocked by the other students as "Krelboynes", after geeky Seymour Krelborn in The Little Shop of Horrors. Jane Kaczmarek is Malcolm's overbearing, authoritarian mother, Lois, and Bryan Cranston plays his disengaged but loving father Hal. Christopher Masterson plays eldest brother Francis, a former rebel who, in earlier episodes, was in military school, but eventually marries and settles into a steady job. Justin Berfield is Malcolm's dimwitted older brother Reese, a schoolyard bully who tortures Malcolm at home even while he defends him at school. Younger brother Dewey is portrayed by Erik Per Sullivan. For the first couple of seasons, the show's focus was on Malcolm. As the series progressed, however, it began to explore all six members of the family rather equally.
It is produced by Satin City and Fox Television Studios (syndicated by 20th Television)