Like many science fiction series aired on major network television, Alien Nation suffered from an abrupt cancellation for which the writers and producers were unprepared. Unlike many science fiction series aired on major network television, it had received fairly solid ratings, so the show-runners, confident that they would have a second season, ended the first on a cliffhanger, with its main characters infected by a virus designed to completely eradicate their species.I can imagine how thankful enthusiastic fans must have been when the novel-series was released following the TV show's cancellation. Dark Horizon is based on the scripts for both the series untimely conclusion, "Green Eyes", and the proposed second season opener, from which the novel gets its name. Though he's not always successful, K. W. Jeter does an admirable job of attempting to unify these two scripts, which were clearly very different both thematically and in terms of plot. His writing is at times very strong--there are a few scenes featuring Cathy, particularly, that are tenderly and vividly written.However, since I've seen the TV movie that was later based on the second script, this doesn't break any new ground. It's very obvious that Jeter's kept very closely to the source material (most scenes and dialog are word-for-word identical to the later movie), so much of this felt repetitive and perfunctory. The few points of diversion from the television movie, particularly the resolution of Buck Francisco's romance with his human teacher, were really the only scenes that made reading Dark Horizon a worthwhile endeavor. It's too bad, since he's clearly a powerful writer, but nevertheless, the place for this book in the franchise has been supplanted. Watch the movie, or read the book, but it's definitely not necessary to do both--you won't be missing anything. ( )