For twelve years Sam has been imprisoned in his head, unable to express his wild ideas or anything else for that matter. Then Sami appears. Outward-going and articulate, she gets on well with everybody. The catch? Sam and Sami are a chimera; genetically distinct parts of the same person. Sam's dad has sheltered him from the savagery of a world where natural food is banished and alternative medicine is illegal. The emergence of Sami changes everything. There's a rumour the Food Police are searching for just such a child. Why? Because myth has it she is to save the world.