The third standalone novel set in Molly Tanzer's magic-infused universe takes readers to World War II–era England where two young women are studying witchcraft. Though once inseparable, competition, secrets, and wildly dangerous magic set them at odds and draw them to terrifying ends.In Northern England during World War II, best friends Jane Blackwood and Miriam Cohen are both studying to join the Société des Éclairées, an international organization of diabolists. Jane and Miriam are as close as sisters, but the pressures of their studies, the war, and the secrets they keep threaten to tear them apart. Miriam learns her parents are suspected of betraying the Société to the Nazis, and her effort to clear their names sends her on a perilous journey to a source of the enemy's power. Jane, afraid of falling behind the brilliant Miriam, believes her only hope to excel lies in a forbidden and wildly dangerous use of the...