Annihilation (Southern Reach #1), Jeff VanderMeer

For years, Area X has remained mysterious and remote behind its intangible border – an environmental disaster zone, though to all appearances an abundant wilderness. The Southern Reach, a secretive government agency, has sent eleven expeditions to investigate it. One has ended in mass suicide, another in a hail of gunfire, the eleventh in a fatal cancer epidemic.

Now four women embark on the twelfth expedition into the unknown.