In N. K. Jemisin's new novel, The Fifth Season, the payoff is astounding. Sure, there's a whopping glossary at the end of the book — two of them, actually — but that simply underscores how much sumptuous detail and dimensionality she's packed into her premise. The story takes place in a land called the Stillness, a tragically ironic name, seeing as how the geography is in constant, violent flux. The entire world undergoes apocalypses on a periodic basis, as regular as weather patterns. In the fractured landscape that houses the sprawling city of Yumenes, that instability has given civilization an equally volatile reality. A caste system scars it. Science and magic have uneasily mixed. And Essun is a small-town schoolteacher whose family has been brutally ripped apart from within.