Presumably the reader is familiar with the concept of "Alternate histories", stories that explore the question of what the present would look like if some key factor in the past had not happened, or had happened differently, than it actually did. This book is comprised of three such stories, each of novella length, in which the "history" that has been altered is the "history" of the Star Trek universe.
The first story, by David R. George III, seems to this reviewer to be a bit unclear on the concept; there seems to be two major changes to the timeline, basically unconnected, so it's difficult to see why they are put into the same alternate history. The first change is that Picard is not rescued in the episode "The Best of Both Worlds", but rather the Enterprise under the command of Riker successfully destroys the borg cube with Picard/Locutus, and Riker remains the captain of the Enterprise. The second change, and the one that seems to have more "alternate universe" bearing, is that Data is successful in saving his "daughter" from the cascade failures that rendered Starfleet's desire to abscond with her moot, and she is taken away by Starfleet. An interesting story, but the dual change in the timeline muddles the issue.
The second story, by Steve Mollmann & Michael Schuster, explores the question of "what if" the planet Vulcan had never been converted to the following of logic by Surak, and remained barbarous and warlike, so that the first contact with earth was made by Andoria rather than Vulcan. A very interesting story with a moderately unsatisfactory ending.
The third story was also an interesting concept; told by Scott Pearson, it explores the question of "what if" an accidental explosion had killed Cyrano Jones and his tribbles before he had the opportunity to spread them about Space Station K7 in the Episode "Trouble With Tribbles", thus resulting in the poisoning of the Quatrotriticale grain and the imposture of Arne Darvin never being uncovered. Unfortunately, this was the worst-written (or at least, worst-edited) story of the three; there are a few editing slip-ups in the previous two stories, but twice as many in the third as in the previous two combined. Things like "helsman" instead of "helmsman", "Betazoid" rather than "Betazed" when referring to the planet itself, rather than a denizen of it, "whom" rather than "who", "looked way" rather than "looked away", "Darvis" rather than "Darvin" when referring to the character who is, after all, central to the story, a comma instead of a period (or at the very least, a semicolon) in the "sentence": "Kamuk, watching Krell stomping toward them, started laughing, Baris turned on him.", "peaking" rather than "piquing" somone's interest, leaving out the word "she" in the phrase "Jensen chuckled as sat down...", the phrase "Baris hurried away as if to make contact emergency sevices", which either needed to lose the "make" or to have the word "with" inserted between "contact" and "emergency", the word "breath" instead of "breathe", the word "get" omitted from the phrase "...needed to back to...".Any one (or even two or three) of these could be overlooked as trivial flaws in an otherwise good story, but the sheer volume of them was more than a bit distracting and definitely made the story less interesting, at least to this reviewer.
Overall, not a bad read, but this book definitely had lots of room for improvement.