Twelve-year-old Mary Hayes can't stand her orphanage for another night. But when an attempted escape through the stove pipe doesn't go quite as well as she'd hoped, Mary fears she'll be stuck in the Buffalo Asylum for Young Ladies forever.

The very next day, a mysterious woman named Madame Z appears at the orphanage requesting to adopt Mary, and the matron's all too happy to get the girl off her hands. Soon, Mary is fed a hearty meal, dressed in a clean, new nightgown and shown to a soft bed with blankets piled high. She can hardly believe she isn't dreaming!

But when Mary begins to explore the strange nearby town with the help of her new friend, Jacob, she learns a terrifying secret about Madame Z's true identity. If Mary's not careful, her new home might just turn into a nightmare.