Cerys is safe in the Kingdom of Aloriya. Here there are no droughts, disease, or famine, and peace is everlasting. It has been this way for hundreds of years, since the first king made a bargain with the lady who ruled the forest that borders the kingdom. But as Aloriya prospered, the woods grew dark, cursed, and forbidden.

A Great Winged One will soon arise and cast his fearsome shadow upon the land. And just as Night slays Day, and Day slays Night, so also shall another Black Witch rise to meet him, her powers vast beyond imagining. So foretells the greatest prophecy of the Gardnerian mages. Carnissa Gardner, the last prophesied Black Witch, drove back the enemy forces and saved her people during the Realm War. Now a new evil is on the horizon, and her granddaughter, Elloren, is believed to be Carnissa's heir—but utterly devoid of power in a society that prizes magical ability above nearly all else.

Orphaned. Trained to fight. Raised to fear the power of Underhill. Secretly in love with a man who doesn’t want me. I’m still just Alli, a.k.a. the half-human orphan fae, but my life is looking up for the first time. It only took me my whole 24 years. But when Underhill - the ancestral home of the fae - shatters, making it impossible for any fae to enter, I’m the only one who knows who did it. A secret that will be the death of me if I do nothing.

Fortuna Sworn is the last of her kind. Her brother disappeared two years ago, leaving her with no family or species to speak of. She hides among humans, spending her days working at a bar and her nights searching for him. The bleak pattern goes on and on...until she catches the eye of a powerful faerie. He makes no attempt to hide that he desires Fortuna. And in exchange for her, he offers something irresistible. So Fortuna reluctantly leaves her safe existence behind to step back into a world of creatures and power.

All magic comes with a price, though, and for years the sisters have been separated. Esther has fled to a remote base in Antarctica to escape the fate that killed her own mother, and Joanna’s isolated herself in their family home in Vermont, devoting her life to the study of these cherished volumes. But after their father dies suddenly while reading a book Joanna has never seen before, the sisters must reunite to preserve their family legacy.