Boston, 1891. Sophia Tims comes from a family of explorers and cartologers who, for generations, have been traveling and mapping the New World--a world changed by the Great Disruption of 1799, when all the continents were flung into different time periods. Eight years ago, Sophia's parents left her with her uncle Shadrack, the foremost cartologer in Boston, and went on an urgent mission. They never returned.

Then Shadrack is kidnapped. Sophia...

It is the summer of 1892, one year since Sophia Tims and her friend Theo embarked upon the dangerous adventure that rewrote the map of the world. Since their return home to Boston, she has continued searching for clues to her parents' disappearance, combing archives and libraries, grasping at even the most slender leads. Theo has apprenticed himself to an explorer in order to follow those leads across the country--but one after...