In this high-stakes fantasy romance, a once-in-a-generation duel to the death between rival witches and dragon riders determines the fate of the source of all magic.

Astrid, the last Nachstern witch and heir to the Queendom of Arturea, has always known she is destined to die. Cursed by a centuries-old covenant, she must duel the heir to the Kingdom of Vatra for the Heart, the source of all magic. With her time running out, Astrid travels into enemy territory to face Prince Zryan, the most powerful dragon rider in eons, armed only with her familiar, her potions, and her wits. If she fails, her queendom will lose its only chance to cure the Blight ravaging its lands and killing its people.

Meanwhile, in the heart of dragon country, Skylar and her traveling troupe arrive in Vatra's capital to profit from the spectators gathering for the duel. Skylar despises the royals, who are responsible for her mother's death at the hands of the King's guard. However, when her best friend disappears—suspected to have been taken in the conscription—Skylar’s search leads her closer to the royals than she ever imagined.

As the duel looms, the fates of Skylar and Astrid intertwine. They must battle a growing rebellion, their own inner demons, and those they love most, to determine if they will save or doom their world.