Sometimes, to get yourself into trouble, all you need to do is go down into the subway.
My sister and I lost each other in the World of the Endurers: those who survived a thousand Disasters that erased other worlds.
The last one was the Polis-Imperium, encircled by several rings of walls. An empire where noble houses accepted the blessing of spirits in order to gain strength.
Now I am one of the Old—omen-bearers of this world, and a divine spark leads me through the Disasters to saving my sister and to the throne of the last Imperium.