Let me preface this review by saying that, although I have not met Dr. Clark, I feel as if we know each other. I am the author of Operation Ivy Bells, another book about deep sea diving, although from an entirely different perspective. I was part of operational saturation diving during the Cold War. I have taken a Mk XI to a thousand feet, and I understand that the Mk XII has been to over 1,800 feet. The Mk XVI simply has to be better in all aspects, although I never dove it. We used hot water suits in our operational saturation diving, and more recently I have used several drysuit models, my favorite being the DUI crushed neoprene model. This novel is fascinating. Personally, I never put much credence in clairvoyance and some of the other psychic phenomena that appear in Middle Waters, but Clark pulled me in, seemingly without effort – Bravo Zulu! The alien angle was fascinating and quite believable within the context of the story. Clark's characters were three-dimensional, and he even managed to generate some depth-of-character for a couple of the aliens who played meaningful roles. I have a couple of negatives that should be mentioned. From time to time within a chapter, Clark suddenly shifts scenes dramatically from one paragraph to the next. This caught me unawares. I would have preferred a break of some kind to warn me. Also, as the story progresses from a specific party’s perspective, suddenly, Clark tells me about the thoughts of another character in the scene without shifting the story point-of-view to that character. It’s a confusing mistake that many first-time novelists make. Had the story not been so very good, I would have downgraded the rating to a 4-star or even less because of this, but the story quality simply trumped these problems in spades! I wholeheartedly award this story 5 stars, and will recommend it to anyone interested in a different take on humanity’s role in the universe, and in deep sea diving and aviation, of course. (Contact me, Dr. Clark, and we can have an interesting dialogue.) ( )