Shorter than most of Robinson's other science fiction novels, this one is set in an imaginary world and is fantasy. It is mysterious and doesn't really explain what is happening or why but is strangely fascinating none the less.
When he came to he was drowning. The water was black and he bobbed up in it swiftly, obscurely aware that it was dangerous to do so, but he was helpless to stop; he tumbled over and swam downward, arms loose and thrusting like tentacles, but it was useless. Air popped out of him in a stream of white bubbles that flattened and shimmied as they squashed upward all clustered around bearing him to the surface.