Everyone in Foss Butcher’s village knows what happens when the magic-workers come. They harvest human hearts to use in their spells. But Foss never expected that anyone would want hers. So when a sorcerer snags a piece of Foss’ heart without meaning to, she is furious. She stomps toward the grand City to keep his enchanted House and demands that he fixes her before she keels over and dies. But the sorcerer, Sylvester, is not what she expected. Petulant, idle and new to his powers, Sylvester has no clue how to undo the heart-taking, or how to do much of anything. Foss’ only friend is a talking cat, and even the House’s walls themselves have moods. As Foss searches for a cure, she accidentally uncovers that there is much more to the heart-taking --- and to the magic-workers themselves --- than she ever could have imagined.