Every four years, two girls are kidnapped from the village of Gavaldon. Legend has it these lost children are sent to the School for Good and Evil, the fabled institution where they become fairytale heroes or villains.

With her glass slippers and devotion to good deeds, Sophie knows she'll join the ranks of past students like Cinderella, Rapunzel, and Snow White at the School for Good. Meanwhile, Agatha, with her shapeless black dresses and wicked black cat, seems a natural fit for the villains in the School for Evil.

But the two girls soon find their fortunes reversed - Sophie's dumped in the School for Evil to take Uglification, Death Curses and Henchmen Training, while Agatha finds herself in the School for Good, thrust among handsome princes and fair maidens for classes in Princess Etiquette and Animal Communication.

But what if the mistake is actually the first clue to discovering who Sophie and Agatha really are?