7. Arc Angel
Anyone who has watched original Trek or Next Gen will readily admit that there never was anything approaching a story arc in it. That is, episodes came and went, self-contained by and large and one rarely led to another (other than the two-parters, of course); in essence, few if any had an appreciable or measurable impact on future episodes. Oh there were the likes of Tasha's death and how that affected among others Data, and Picard's time spent as an unwilling guest of the Borg certainly had an effect on him and was in fact taken all the way into the eighth movie. But as a casual viewer, you could generally look at a Star Trek TNG episode without having seen any prior ones and, if you so desired, without ever seeing another one, and you would come away with no real sense of loss or confusion. Certainly not the idea that you had, as it were, walked in right in the middle of the movie. Babylon 5 aimed to change all of that. It would not be fair to say that JMS invented the story arc --- I'm sure people will point out there were other shows using such a device before he came along. But he was certainly and without question the first one to use it in a science-fiction drama, and the first to utilise it so skilfully and successfully, and make it an intrinsic part of the show. By midway through season two of Babylon 5, if you hadn't kept up to speed you were going to be lost. It was definitely a show where you needed to see, and understand, what had gone before. Perhaps due to this requirement, the show was never one to use those "previously on..." segments, even at the opening of a new season. If you were watching Babylon 5 you were expected to be invested in its storyline, know its characters and be up to date on most if not all of the plots and subplots. Let's be fair: there was so much going on in the show that were there to be a quick recap before each episode, even each season, half the episode would be used up. But Babylon 5 was beset by problems throughout its run, despite winning two Hugo awards and two Emmys, something unthinkable for a sci-fi series at the time. Cast changes midway through seasons, threats of cancellation and interference from network executives all plagued JMS as he struggled, with his top-drawer team, to create the world, the galaxy, the story that he had envisaged that morning in the shower. Right up to its last season Babylon 5 was in danger of getting the axe, which seems amazing now when you see how it's taken its place in the history of science-fiction TV drama.