The story of a man with autism and his difficult decision to undergo an experimental cure.
Although science fiction in the sense of being set in future and the cure needing science, that is not the centre of the book.
The central character is in a different place on the spectrum than anyone I know but Moon's son has autism and the character feels real. It is told mostly in first person from his perspective. Even if inaccurate, I found myself thinking from this perspective for at least a few minutes after each reading session.