Pirouette Leiter, the Puppetmaster's Apprentice, is given the most important and dangerous job of her life: to build a wooden assassin for the tyrant of Tavia. The Margrave of Tavia hasn't emerged from Wolfspire Hall in over a decade. His palace has been a silent citadel on the hill overlooking the village, until a peculiar commission reaches the puppetmaster and his daughter—they must make one hundred wooden soldiers for him as quickly as possible, or the puppetmaster will be imprisoned in the dungeons of Wolfspire Keep. Pirouette has no choice but to obey the young ruler's strange whims to save her father, all while hiding a dangerous secret of her own—she was once a puppet, brought to life by the light of the blue moon. When the Margrave requires that Pirouette craft him a puppet the likes of which the world has never seen—an intricately carved, life-sized assassin—he doesn't stop there. He demands she bring her ultimate creation to life. Fighting against dark magic and racing against the rise of the next blue moon, she can't help but wonder, is she making a masterpiece ... or a monster?