From a review on the (well-known big river) website, by William F Twist:
First, I want to say that I really, really wanted to like this book. I really did. But there were so many factual problems with it, that I can't take it seriously.
First and foremost, the author mentions on several pages that the explosion aboard K-129 was monitored by a US early warning satellite. The problem with this is that according to "Guardians, Strategic Reconnaissance Satellites" by Curtis Peebles (Presidio Press, 1987. ISBN 0-89141-284-0), a comprehensive work on intelligence satellites from the beginning until 1985, there were no early warning satellites in operation in March 1968, when K-129 went down. The low orbit MIDAS follow-up program was cancelled in 1966 (due to problems with coverage and false alarms), and Project 949, its geosynchronous replacement, wasn't launched until August of 1968. So, it couldn't have been been monitored, because we didn't have the capability at the time K-129 sank.
Also, Sewell claims that the sailing was timed to prevent it from being detected by photoreconaissance satellites, but again we run into an issue: At the time, *ALL* US photorecon satellites were 'film return' types. In other words, they imaged what they saw directly on to film, and when they were done they returned that film back to Earth to be developed and interpreted. After they ejected the film, they were essentially useless. Referring back to "Guardians" again, we find that the Russians didn't have to try very hard to evade them: Launch 1968-5 was on January 18th, and had a lifetime of 17 days. That put the return back on February 5th. K-129 sailed on February 24th. The next US launch wasn't until March 13th, almost a week after K-129 sank.
Also, the author claims that K-129 was followed by a Permit class submarine, and that this sub recorded the acoustical signature for later processing on land-based Cray supercomputers. Remember, this is 1968. Seymour Cray didn't found Cray Research until 1972, and the first Cray-1 wasn't completed until 1976. Now, I have no doubt that the boat could have been followed, and its signature recorded for processing back on land, but if the author makes a mistake like this (and the aforementioned ones), how can you trust the other claims?
Shame - it sounded such a good read. Anyway, I'll probably buy a copy.