Mary Broderick has never been that good at doing what she was told. Her parents, her teachers, everyone and everything, have always told her that being unwell was just something she had to get used to. The more they tell her, the more it makes her want to know why. When a new boy comes to school, a curious boy with strange habits and no obvious conditions, Mary finally finds a mystery she can sink her teeth into. She decides she's got to find out about this boy no matter what it takes, even if it kills her.