The third book in the Ender sequence, this one is much broader in scope. Lusitania is still the setting of a large portion of the book. We are also introduced to Path, a planet settled by the Chinese, where a portion of the population is "godspoken": highly intelligent but also displaying signs of obsessive-compulsive disorder. Various characters are now working to avert the destruction of Lusitania, which would wipe out the only two known non-human intelligent species. Questions arise about the nature of intelligence, and how to decide between the survival of two species. It's hard to give a summary of the book, but it was thought-provoking and I enjoyed reading it. I'm impressed with the way Card is able to use science fiction to discuss theories about human nature and good and evil.
One complaint—the edition I had had quite a few typos in it, sometimes omitting entire words.