Neal Shusterman's Unwind tells a gruesome tale of a society addicted to a supply of human spare parts. Medical technology allows safe transplants of eyes, organs, even limbs to replace broken or diseased originals. And the new ones come from teenagers whose parents have chosen to "unwind" their kids, usually because of the trouble the children have been getting into. Or because they are orphans, or otherwise unwanted.
Connor and Risa meet up when they go on the run, and they both have to learn to cope for themselves and learn how to disappear and find help from people appalled by the situation. The first part of the book is more about their personal situation, with Connor especially finally learning to control some of the impulsive behavior that drove his parents to unwind him. Shusterman also looks at how the parents' decide this, echoing and amplifying the feeling most parents feel at least momentarily during their offspring's more trying episodes. It's a true example of science fiction; taking a thought about "what if" and "if this goes on" and running with it to see how it plays out, using real people and solid motivations. It's not a prediction, but it is an exciting and suspenseful story.
Oh, for the squeamish, it's the ideas that are gruesome; we don't see a lot of gore and such. B+