Australian author Justine Larbalestier's Magic or Madness trilogy challenged Reason - that is, to say, a teenage girl named Reason who spent her life with her cheery mother, until her lovely mother went a little mad.
When her mother fell apart, Reason finally realized that the stories her mom told her were true. Magic exists, and it runs through the veins of all of the women in her family. Either they use their magic and die young, or they repress it and go mad. One way or another, whatever path Reason chooses is bound to lead her to tragedy.
Her grandmother, who is depicted as a villain in all of her mother's stories, takes Reason in when she has no other place to go. Reason then meets her gran's neighbor, a boy her own age, and Jay-Tee, a girl who lives in New York - which magically appears outside of her grandmother's door.
The story continued in Magic Lessons, when the stakes were raised and the powers of the main characters tested. The final book, Magic's Child, delivered plenty of surprises. The title itself is a huge spoiler, obviously. The events leading up to the blessed (or not-so-blessed) event push Reason's sanity and strength to the brink.
In the final book, each character got his or her moment in the spotlight as the story bounced back and forth between locations and viewpoints. I enjoyed Reason's travels around the world, confirming the presence of other doors and introducing her to another generation of magic-users. (Can you say spinoff?) I found myself liking Jay-Tee more and more as the story progressed. Even Sarafina has a memorable scene in which she creates butterflies. Such a childlike innocence about her then, making her greedy demeanor and evil actions only a short while later all the more scary.
Plus I like butterflies.
As a bonus, because Reason travels back and forth between Australia and New York and the various characters use slang from their native countries, each of the Magic or Madness books includes a glossary of terms.
Read the trilogy in the proper order:
Magic or Madness
Read my interview with Scott Westerfeld and Justine Larbalestier.