When he goes to high school, his favorite class is English literature. He doesn’t know how to make friends and feels lonely: he is a "wallflower". Unexpectedly, a boy in a higher class, Patrick, and his stepsister Sam connect with him and bring him into their group of friends. He goes out with them and has many new experiences: friendship, parties, drugs, love, sex, etc. For example, he successfully defends Patrick from five boys and he helps his sister Candace when she gets pregnant by her boyfriend. All this he writes down in the "letters to a friend" that make up the book.