Illuminating all Orphan Towne with a newfangled invention, "the light bulb" is enough excitement for Junior Engineer (Third Class) Alvin Esker, but after discovering Hana, a peculiar girl-who-can't-exist, his familiar world of lectrics and lunches flips on its pole. Before he knows it, he and Hana have triggered an experiment that threatens the survival of Orphan Towne-and possibly a continent. They embark on a trek to the top of the earth, on the trail of the last discovery of the Last Astronomer, to stop the doom they unwittingly caused ... assuming they don't die.