The series is about a boy named Malcolm (Frankie Muniz), who is revealed in the first episode to be a genius with an IQ of 165, which places him in a class for gifted students (also known as "Krelboynes"), originally taught by Caroline Miller (Catherine Lloyd Burns). He is the third-born child in a comically dysfunctional working-class family of four, and later, five boys, of Lois (Jane Kaczmarek) and Hal (Bryan Cranston). As of the first season, their delinquent oldest child, Francis (Christopher Kennedy Masterson), has been sent away to military school, while younger brothers Reese (Justin Berfield), Malcolm and Dewey (Erik Per Sullivan) remain at home with their parents. With Francis away, Malcolm becomes the middle child of the family. In season four, the character Jamie (James and Lukas Rodriguez) was added to the show as the fifth son of Hal and Lois. The show's early seasons centered on Malcolm dealing with the rigors of being an intellectual and enduring the eccentricities of family life.