When Will and Bet were four, tragic circumstances brought them to the same house, to be raised by a wealthy gentleman as brother and sister. Now sixteen, they've both enjoyed a privileged upbringing thus far. But not all is well in their household. Because she's a girl, Bet's world is contained within the walls of their grand home, her education limited to the rudiments of reading, writing, arithmetic, and sewing. Will's world is much larger. He is allowed—forced, in his case—to go to school. Neither is happy.

So Bet comes up with a plan and persuades Will to give it a try: They'll switch places. She'll go to school as Will. Will can live as he chooses. But once Bet gets to school, she soon realizes living as a boy is going to be much more difficult than she imagined.