There aren't enough superlatives. At least, none that I can use without causing the reader to assume that I'm some callow reader who is quick to throw out the "best book evah!" response to any book that I've enjoyed. I don't; this is the first time I've ever been tempted to do so, and I won't even do it here. But while this may not be the best book I've ever read, it is unquestionably the best Star Trek book I've ever read, and I suspect that I've probably read in excess of three hundred at this point.
The book is based on an episode from the Deep Space Nine series, one of the early episodes in which a Cardassian boy is found who has been adopted by Bajoran parents; it turns out that his Cardassian father is still alive, had thought him dead, and shows up on Deep Space Nine to reclaim him. The episode is well-handled, giving fair play to both sides of the argument as to whether the boy belongs with the only parents he remembers (he's sixteen, and has been with them since he was two) or his biological father, who did not abandon him and was crushed when he thought his son died in the same bombing that his wife did, and who is delighted to find him still alive, even though it will be a political inconvenience that his opponents can exploit. But in the end, Commander Sisko is chosen as an arbitrator of the case, and being a father himself, rules in favor of the boy's biological father.
I've always considered that to have been a terrible decision, possibly the worst thing that Sisko ever did, and it was pleasant to see that this author agreed with me. But beyond that rather shallow sense of satisfaction, this book (which follows the young man's life from that point until the "present", well after the end of the series) does an absolutely fabulous job of making plausible extrapolations to the story line, and a wonderful job of character development. It is an extremely powerful story, and one that everyone, Star Trek fan or not, should read. It touches on so many issues -- war, revolution, democracy, family, loyalty, friendship, kindness, cruelty -- and handles all of them with a very adept, touching evenhandedness.
If I was allowed to rate this book at more than five stars, it would definitely get six. Maybe seven.