The main plot of this book is Star Trek at its best, giving a very close look at a basic truth: the reason for most aggression is fear. Unfortunately, the subplot involving Dr. Crandall, the civilian observer and general pest, was not up to the standards of the rest of the book; it was neither original nor believable, and was, in fact, pretty well pointless. The concept that the "outsider" from off the Enterprise, whether an Admiral from Starfleet or a civilian scientist, proves to be difficult and troublesome is done so often in Original Series episodes and books that it is trite beyond words, and the concept that someone as utterly worthless as this clown was portrayed throughout the book could have such a sudden change of heart and selflessly risk his life to save the day is completely out of the realm of possibility. If you wanted him to get to that point eventually, he needed to either have been portrayed with SOME redeeming value earlier, or else have been given more time to digest his transforming experience before acting on it. As it was, people just don't work that way. Not even in a gloriously optimistic place like the Star Trek universe. This cost the book a star, but it was still an excellent book, very thought-provoking, and maintaining much of the feel of an Original Series episode.