The Long Price Quartet is a series of four fantasy novels written by author Daniel Abraham. The series is set in a unique world where the economy and society are deeply influenced by the use of powerful, magical entities known as prices. These prices are tied to the emotions and desires of the people, creating a complex interplay between magic and human relationships. The quartet includes the books A Shadow in Summer, A Betrayal in Winter, An Autumn War, and The Long Price. Each novel explores themes of love, power, and sacrifice, following the lives of characters who navigate the challenges posed by their society's reliance on these magical prices. The series is noted for its rich world-building and character development.