Aliens have attacked Earth twice and have nearly destroyed the human species. To make sure humans win the next encounter, the world government has begun breeding military geniuses and training them in the arts of war. Early soldier training takes the form of 'games,' and Ender Wiggin is a genius among geniuses; he outmaneuvers each opponent he encounters. He is smart enough to know that time is running out, but he has not yet played a game as intricate as trying to save the planet.