When Antonia Dillon takes a student job as a peer counselor at her middle school, she finds herself in a counseling session with Jazz Luther, a punker who appears to be rude and intolerable. Antonia plays by the rules; she dresses conservatively and devotes herself to getting good grades in school. Jazz, on the other hand, wears black lipstick, has piercings and tattoos, and rebels against everything. These two seemingly opposite teenagers appear to have nothing in common, yet during the course of their counseling sessions they find themselves opening up to each other and becoming friends. Antonia and Jazz both gain emotional maturity as they learn to relate to each other and help each other cope with their problems. Each helps the other view their own issues from a different perspective, and by the end of the novel they have both grown up in surprising ways.

Antonia and Jazz have backgrounds as different as night and day, and the way they relate to their families colors the way they react to the world. Antonia Dillon appears to be happy and well adjusted: she performs well in school, she never questions authority, and thus she fits the socially accepted definition of normal. Jazz does not fit the socially accepted definition of normal. She dresses in a radical manner, she rebels against authority, and she appears to be angry with everyone. Underneath their exteriors, however, these two girls have secret pains and desires that unite them in a common bond. By the end of the novel, the term "normal" takes on a new meaning, and the way someone looks and dresses has little meaning.