sentences:  The novel touches on such themes as the fear of human annihilation, especially nuclear annihilation; the then-imminent changes in sex roles; the power of America; the question of whether human beings are basically good or evil; and the existence or non-existence of God.L'Engle's narrative shows the same respect for adolescent intelligence that is prominent in "A Wrinkle In Time" and its sequels.For example, Zachary discusses anthropology knowledgeably with Vicky, and Classical music is important in Vicky's life.