Bree Deringer, Olivia Hayes, Kitty Wei, and Margot Mejia have nothing in common, At least that's what they'd like the students and administrators of their elite private school to think. The girls have different goals, different friends, and different lives, but they share one very big secret: They're all members of Don't Get Mad, a secret society that anonymously takes revenge on the school's bullies, mean girls, and tyrannical teachers.