This keeps coming up a lot in different threads so I decided to make one specifically addressing it. I think we can all agree Star Trek is a kind of space opera, and that it fits into a specific history with certain technologies as well as a given list of races and polities. But I think we can all agree this is not enough. For example, I am a big fan of the re-imagined BSG. But taking that same idea and putting it into Gene Roddenberry's universe--would it be Star Trek? Song-type androids wage a surprise attack on the Federation, wiping out all but a collection of civilian spacecraft and one lone starship to protect them and find some new home? Whereupon we find the long-lost world of the original humanoids and learn they suffered a near-identical fate when developing androids of their own? With the news some entity or entities like Q or the Organians are subtly shifting events to make sure the survivors have a chance but perhaps learn not to make the same mistakes all over again? Don't think I'm the only one to say "That doesn't seem like Star Trek to me." But why not? Just as if you assume that five centuries after VOY the Federation has become a despotic dictatorship, but a band of criminals and political prisoners find a sentient starship far more advanced than anything anyone has ever seen before. They decide to fight back, try to bring down the Federation! Well, that is Blake's Seven. A good show. I liked it a lot! But even the premise lacks an ineffable something that would make it Star Trek. What is that ineffable something, though? That something that TOS, TNG, DS9 and VOY all had. The movies as well, even the ones that weren't that good. Haven't read all the novels, not by a long shot, yet the ones I've read "feel" like Star Trek to me even if I don't like them (some of the early adaptations of TOS episodes oddly enough do not). So, what is that something that makes a show or movie or book Star Trek?