When Milo's uncle and Tilly's grandfather are poisoned by a mysterious copy of The Wizard of Oz and fall into a deep sleep, Milo and Tilly travel to the Emard City to find out who is behind the poisoning.

"Twelve-year-old Minerva Keen forms a detective club to uncover who is poisoning residents of her storied Chicago apartment building, knowing that any one of her neighbors could be the poisoner--or the next victim"--

In the Aramtesh Empire scent is all important, and seventeen-year-old Rakel has a way with perfumes which she hopes to use to delay her father's inevitable death; Ash is a member of the imperial bodyguard, assigned to the crown prince Nisai's bodyguard; now they are all brought together on a caravan to an outer province, seeking a rare flower that can cure the poisoned emperor--but when Nisai himself is poisoned Rakel and Ash smell like the chief...