Eric Calhoune is known to his classmates as "Moby" because of the extra weight he has carried since grade school.  Though his mother is young and athletic, he has inherited the body type of the father he's never known.  Now, in high school, the fat is turning to muscle under the discipline of hard swim team workouts.  But that transformation has been slow in coming, since for some time Eric has taken on a private commitment to "stay fat for Sarah Byrnes."  Sarah, whose name is a painful pun, was severely burned as a small child not, as we are given to believe early on, because of an accident, but because of a cruel and crazy father who stuck her face and hands into a woodstove in a moment of rage.  She has lived with him and his threats for some time; that and her disfiguring scars have made her tough, smart, and self-protective.  Eric and she became friends as social outcasts.  Well-matched intellectually and in their subversive wit, they write an underground newspaper together.  Sarah, however, lands suddenly in the hospital, speaking to no one, making eye contact with no one.  Eric faithfully visits her and, per nurses' instructions, keeps up a running one-sided conversation as if she could hear him.  As it turns out, she can.  She is faking catatonia because the hospital is a safe place, and she has chosen this as an escape route from her father.  Eric and a sympathetic coach/teacher go to great lengths to find Sarah's mother-who, it turns out, can't bring herself to be involved in her daughter's life because of her own overwhelming shame.  Ultimately the father is apprehended, and Sarah, nearly eighteen, is taken into the coach's home and adopted for what remains of the childhood she bypassed long before.  In the course of this main plot, other kids enter the story and in various ways come to terms with serious issues in their own lives, some of which are aired in a "Contemporary American Thought" course where no controversy is taboo.