The Alexandrian Society, caretakers of lost knowledge from the greatest civilizations of antiquity, are the foremost secret society of magical academicians in the world. Those who earn a place among the Alexandrians will secure a life of wealth, power, and prestige beyond their wildest dreams, and each decade, only the six most uniquely talented magicians are selected to be considered for initiation. Enter the latest round of six: Libby Rhodes and Nico de Varona, unwilling halves of an unfathomable whole, who exert uncanny control over every element of physicality.

In a shabby house, on a shabby street, in the new capital of Madrid, Luzia Cotado uses scraps of magic to get through her days of endless toil as a scullion. But when her scheming mistress discovers the lump of a servant cowering in the kitchen is actually hiding a talent for little miracles, she demands Luzia use those gifts to improve the family's social position.

In modern-day Manhattan where we lay our scene, two rival witch families fight to maintain control of their respective criminal empires. On one side of the conflict are the Antonova sisters—each one beautiful, cunning, and ruthless—and their mother, the elusive supplier of premium intoxicants, known only as Baba Yaga.

Once, there were four worlds, nestled like pages in a book, each pulsing with fantastical power and connected by a single city: London. Until the magic grew too fast and forced the worlds to seal the doors between them in a desperate gamble to protect their own. The few magicians who could still open the doors grew more rare as time passed and now, only three Antari are known in recent memory—Kell Maresh of Red London, Delilah Bard of Grey London, and Holland Vosijk, of White London.

Cambridge professor Emily Wilde is good at many things: She is the foremost expert on the study of faeries. She is a genius scholar and a meticulous researcher who is writing the world’s first encyclopaedia of faerie lore. But Emily Wilde is not good at people. She could never make small talk at a party—or even get invited to one. And she prefers the company of her books, her dog, Shadow, and the Fair Folk to other people.