En route to a new boarding school in Dublin after she was caught trying to pawn her father’s old watch, Margo (white) finds herself traveling to a world she didn’t know existed. On the train with her is Moon, a boy Margo’s age with a crescent moon tattoo on his face. Moon is Lunati, a member of a nomadic ethnoreligious group that has mostly been killed off. He’s also a salesman—someone who travels between worlds buying and selling resources—yet has never heard of Earth. With an offer to help her find her way home, Moon takes Margo to a boarding house where she learns that time passes differently in each world, and that a wealthy world called Semper has restricted interworld travel and created a dictatorship to tamp down the other worlds’ revolt. When Moon and Margo realize that the Southern Guard of Semper is pursuing Margo, they join with members of a resistance group who believe that war is imminent and that Margo—or, perhaps, her father’s old watch—is a weapon. The first in a duology, this swiftly paced novel features outstanding, original worldbuilding; fascinating and complex characters; and a gratifying romance. Though it ends on a cliffhanger that hints at adventures and discoveries ahead, this volume feels complete and satisfying in its own right. (Age 14 and older)