This series has already won two well deserved Hugo awards. I hardly want to say anything about the plot, for fear of spoiling some of the epic reveals at the end of the first volume; let me say only that this one is a dark, heartbreaking masterpiece, adding new layers of understanding and complexity to this astonishing world. N.K. Jemisin is a powerhouse. I plan to read through her entire collection of work over the next few years.