This is a novel about the interactions between humans and dolphins. There was something that bothered me for a while. There are long sections of the story told from the point of view of the dolphins. It is clear that the author bases the novel on research that indicates that dolphins may have intelligence on par with or even exceeding the intelligence of humans. I started being irritated, though, that the author was presuming to understand how the dolphins saw humans and how they saw one another. After all, how could he put himself in the minds of dolphins? At best it was highly speculative. When I started using the word speculative to describe my criticism, though, I started to change my mind. I am a great fan of speculative fiction and especially the kind of speculative fiction called science fiction. If you peruse my bookshelves you will see that I most certainly do read other genres though. When I started reading this book I had every expectation that it was from one of those other genres. I am not sure how I had it categorized in my mind, perhaps as just literature. The more I thought of how speculative these passages from the point of view of the dolphins were, though, the more I realized that it was science fiction. It was not marketed as science fiction and there was nothing to indicate that it was science fiction before I started reading it, but it was science fiction anyway. Once I understood that, my irritation disappeared and I decided that it works quite well as science fiction. As I continued to read there were references to ancient Atlantis and that made it verge on fantasy, but I don't think it went so far in that direction that it was taken out of the science fiction realm. On finishing it I decided that all in all I quite enjoyed the book. It was only that I was getting science fiction with absolutely no expectation of science fiction that put me off at first. By the way, the dolphins are portrayed as well disciplined and cooperative members of a society. This shows very well when they rescue a man who fell overboard in midocean. They approached the task of rescue as if they were a well organized military unit.