We open with several pages of legalese explaining that it is against the law to have children with people who have either 100%, 50%, or 25% of the same genetic code as yourself. At the same time we see Tim Robbins flying over a vast desert, which surrounds the city of Shanghai. Clearly something has happened, something bad. We are never told what this something is. We are given hints that sunlight is bad-so bad that everyone now works at night and sleeps during the day. We are also told that clones and test tube babies are common. And most…