The book was ok, and I enjoyed it for the most part. I’m not a SCUBA diver, nor am I a Marine
Biologist or Zoologist. The character in the book used items in his diving gear for various purposes in the book. I had no idea what these items were, what they looked like, or what their actual use for diving was. I did stop reading and researched the items, but still didn’t completely get how they could be used by the main character since I’m not a diver. I am not familiar with the anatomy of a Sperm Whale, but tried to research it as its germane to the story. If the author would simply have put a short glossary of diving equipment in the book as well as a diagram of the internal portions of a Sperm Whale this book would have been so much more enjoyable and easy to follow. I would still recommend the book, but those readers unfamiliar with diving equipment and whale anatomy may need to have Google ready for research.