Margaret centers on a 17-year-old New York City high-school student who feels certain that she inadvertently played a role in a traffic accident that has claimed a woman's life. In her attempts to set things right she meets with opposition at every step. Torn apart with frustration, she begins emotionally brutalizing her family, her friends, her teachers, and most of all, herself. She has been confronted quite unexpectedly with a basic truth: that her youthful ideals are on a collision course against the realities and compromises of the adult world.